Fascinating questions being raised here. Here are my non-expert answers, assuming a 25-year time horizon.
1. 6
Text-adventure games and gamebooks will be implemented as interactive audiobooks, played on hardware such as the Amazon Alexa (like in the Skyrim: Very Special Edition trailer).
As Mathbrush pointed out, this already exists. I just did a quick Google search for “Alexa gamebook” and found several products that seem to fit the bill. But since the prompt asks for a grade based on how likely it is and to what extent, I gave a moderate grade based on the fact that I don’t anticipate these projects will ever become very common or popular, even compared to traditional text adventures and gamebooks, which already are not very popular.
The existing ones that I found have, at most, a few dozen reviews on Amazon. And my thinking is that an interactive audiobook is, by its nature, even more of a niche product than a traditional text adventure or gamebook. Interacting with text on a screen is convenient because the reader can go at their own pace and reread stuff if they want to.
Of course, an audiobook is convenient in its own way - you can easily listen to it while doing something else - but that advantage is probably lost when it concerns an audio gamebook that demands a higher level of attention and engagement from the listener.
Thus I don’t foresee a huge interest in this type of thing, because it’s a medium that seems to offer less inherent advantages than adjacent media for most prospective consumers. The exception would be sight-impaired people.
On the other hand, I can think of one “dark horse” contingency that could turn audio gamebooks into a smash hit: the invention of a brain-computer interface that allows users to process digital audio at the speed of thought rather than the speed at which it was recorded. But I’m not so sure about that becoming widely available in the 25-year time horizon I set. Maybe within 50 years.
2. 4
Interactive books, such as gamebooks and choose-your-own-adventure books will achieve mainstream popularity thanks to e-books.
I’m going to interpret the term “e-book” more narrowly than some others here have done, and assume it refers specifically to the kind of thing you can get on a Kindle: a work of ~100% text buttressed by absolutely no interactive user interface, where the only interactivity is provided by the reader moving from one page to the next in classic CYOA style.
That kind of thing is indeed being sold on Amazon already, and there’s a decent market for it. A quick search for “choose your own adventure” on the Kindle store revealed many titles with hundreds, often thousands of ratings. And a product that has been rated by thousands has probably been read by tens of thousands at least.
Does this qualify as mainstream popularity? I would say no, but admittedly, it depends how one defines mainstream.
Do I expect these types of products to become much more popular than they currently are? No. They’re on Amazon and easy to find. I think they’ve reached their audience and will be lucky to maintain it.
3. 8
Text-adventure games will start to leverage AI more as a content generator or a ”dungeon master”, constantly generating new content and adapting to the players’ actions, such as with AI Dungeon.
It should go without saying that AI is in its infancy and will become more capable over time; presumably this includes creative AI as well. It will not be surprising when AI adventure-generators become sophisticated enough to tell cohesive stories and interpret user input faithfully.
But it also bears mentioning that the discipline of humans using AI for creative purposes is also very much in its infancy. A lot of people still think of this as a binary proposition: either a human author or an AI-generated environment like AI Dungeon. It seems to me that there is much untapped potential for humans to collaborate with AI, actively curating its output to suit their artistic vision, to produce works of finite length.
With that in mind, I’m going to speculate that (at least within the next 25 years - all bets are off if we were talking a century or two) there will be much expansion in the use of AI for constant content generation, but even greater expansion in the use of AI as a step in human authors’ creative processes.
4. 5
Text-adventure games will implement AR and VR to complement the text-display (maybe in the style of Matrix’ “you see the text everywhere around you” or by way of pop-ups: images, characters, videos, “holographic” depictions of events, as seen in many sci-fi/cyberpunk detective works).
I don’t expect much from VR. It was cool for a while in the 90s, then the novelty wore off and people realized it was a pain to use. Now it’s cool for a while again but still as much of a pain. The novelty will wear off again.
AR seems more promising, and has plenty of applications in gaming, but it seems to work at cross-purposes to most forms of text-based gaming. The point of AR is that it allows digital graphics to be superimposed on the real world. This doesn’t seem like a very good fit for a genre that depends upon the player reading text and imagining a whole different world.
That said, cyberpunk is hot. As it becomes easier for common folks to develop content with AR elements, text adventure hobbyists will inevitably create cyberpunk-themed AR games specifically to take advantage of the aesthetic. The same thing may be true for other genres that synergize especially well with an AR presentation because it simulates something that you would experience in the fictional universe. So, basically, we’ll see AR being used to simulate worlds in which a character would be using AR.
5. 2
Hyperfiction stories and platforms (such as Twine) will achieve mainstream popularity.
I’m going to assume that hyperfiction, in this context, is synonymous with hypertext game.
This is another question that really depends on how one defines “mainstream.” I’m beginning to think I have a loftier idea of what mainstream popularity entails than other people do. In my mind, if something hasn’t reached at least a million people, it’s nowhere close to having mainstream popularity.
Have a million individuals played some form of hypertext game within the past few years? I doubt it. If so, I’m woefully out of the loop, so please tell me about it.
Is the hypertext hobbyist community growing? Probably, but I see no indication of rapid growth. So barring some unexpected cultural shift that elevates the virtues of hyperfiction (whatever those virtues may be) to a place of as-yet unknown reverence, this seems like a nope.
6. 4 and 9
Hyperfiction and point and click games will implement AR and VR to at least moderate success.
Are we talking about technical success (i.e. producing a fun or otherwise artistically meritorious game) or popular success (i.e. using AR and/or VR to reach a moderate audience)? I’m going to assume the former, mostly because I don’t want to answer the latter, since I think “moderate audience” is even harder to define than “mainstream popularity.”
Again, I’m going to focus on AR.
For hyperfiction: 4. As with question 4, I don’t see a lot of synergy between AR and text-based media, except for specific genres like cyberpunk - and even then it might be a PITA to read. There would be a tradeoff between ease of use and aesthetic impressiveness.
For point and click: 9. Now here’s a combo that makes sense, because point and click is a model that can actually take advantage of AR’s ability to involve the real world. At some point, it will be possible for AI to use a camera to reliably recognize household items. From there, it’s a short conceptual leap to a point-and-click game set in one’s own house. Maybe a digital item will be scripted to appear behind your drapes or in your toaster oven.
7. 1
Visual novels without text displays will become popular (being like illustrated audiobooks or interactive cartoons or comic books with voice acting).
Many visual novels do include full voice acting already, but they still have text alongside it, and there’s a reason for that. People choose to read visual novels because they like what the format offers: you look at words and images on a screen and process them at your own pace. Mess with that, and you mess with the appeal.
If a visual novel became like an illustrated audiobook, that would not be a very compelling synergy, because it loses some of the main benefits of both media. It can’t be read at one’s own pace like a traditional visual novel, nor can it be fully experienced simply by listening to it while perhaps doing something else or relaxing with one’s eyes closed. In these respects, it’s the worst of both worlds.
Something like a “comic book with voice acting” might work. But at that point, I would consider it a totally separate format from a visual novel.
Same caveat as question 1: if it becomes possible to process digital audio at the speed of thought, then that changes everything I just said.
8. 2
Visual novels will fade out of popularity and be replaced by more cinematic interactive stories, the likes of Detroit: Become Human.
Visual novels have been around since at least the mid-80s. But even today, a well-received VN can sell hundreds of thousands of copies, and it’s not clear to me that the market for them has even weakened at all. Take a look at this table from Wikipedia:
Coincidentally, I’m 49% sure that the last time a VN did something truly innovative on the design side was YU-NO in 1996. By this time, VNs were already technically unsophisticated compared to other types of commercial video games, and the gap has gotten vastly wider since then.
Bigger-budget video games with cinematic sequences and interactive narrative elements in the vein of Detroit are nothing new either. If they haven’t tanked the demand for VNs yet, I doubt that they will anytime in the foreseeable future.
9. 4
VR Visual novels, such as Tokyo Chronos and Koikatsu VR, will become popular.
As above, I believe VR gaming is mostly a fad. That said, VNs are more likely than the other types of media asked about here to be able to achieve at least a temporary boost in popularity by taking advantage of the fad. The synergy makes sense: VR can put the player into the metaphorical shoes of a character interacting face-to-face with other characters, as constitutes the bulk of most VNs, which might be pretty cool. And since VNs have decent commercial prospects, studios with deepish pockets are still developing them; they have the resources to design polished products for VR right now.
As a side note, Koikatsu as an example of a VN seems like quite a stretch to me.
10. 1/???
Visual novels have reached their zenith state and will be the most popular form of interactive literature just as they are.
I’ll treat these two propositions separately.
Visual novels have reached their zenith state: 1. This may sound like an odd position to take since I already opined that not much innovation has happened in the medium since 1996. But even so, there are tons of indie VNs devs active today; tools like Ren’py have made it possible for anyone with some spare time on their hands to make their own VNs. Someone will come up with a paradigm-expanding new idea, eventually. Maybe it’s already out there but just hasn’t caught on yet.
…and will be the most popular form of interactive literature: impossible to evaluate, interactive literature is too difficult to define, and attempting to do so would go way beyond the scope of this answer.
11. 7
Visual novels will implement AR (Augmented Reality), and be readable/playable with, for example Google Glass.
I’d expect this to be a stronger trend among VNs than among text adventures or hyperfiction, mostly because VNs collectively have more money behind them and can afford to experiment. But the synergy also seems much stronger, since the typical VN is more about interacting with characters and less about exploring locations and using objects; I can easily see a VN that uses AR to superimpose its characters into the player’s real-life location.
12. 1
“True” gamebooks, such as the Fighting Fantasy series, will achieve mainstream popularity.
What shall be was. What was shall be.
I predict that in the 2080s, after many years of libertine ethics dominating the public sphere, the rise of a new political coalition will usher in an era of social repression and moral panic. In this fraught environment, someone will rediscover the long-lost Fighting Fantasy series and loudly decry it as the work of Satan himself, which will naturally encourage young people all over the world to get their hands on it. Thus oldschool gamebooks will undergo a renaissance on a scale that we can scarcely imagine.
But it won’t happen within the 25-year time horizon I set for my answers, so 1.