I prefer retro hardcore identity: player = PC.
In any type of interactive fiction, we as writers are always struggling to maintain the suspension of disbelief ( AKA immersion ).
At a minimum, we are asking the player to believe that they are in another environment.
It is an even greater suspension of disbelief for the player to believe that they are another person in that environment
IOW, if player = PC, the player has to believe one thing. If player <> PC, then the player has to believe two things. ( Or you can count with any granularity you like, but it is still one more thing that the player has to believe. )
The more times that the player has to suspend disbelief, the greater the chances that the player will ‘fall out’, or lose their immersion.
Granted, when player = PC, the writer has to do more work. When other characters greet the player, or refer to them, the writing has to have a certain everyperson character to it. ( When the rickshaw driver greets the player, he can’t use “Sir” or '“Ma’am”. He has to resort to something like ‘stranger’ or ‘honored visitor’ ) The writing can very easily become clunky. It is harder to do it well.
But the writer is the one who is supposed to be doing the work here, not the player. That is the central point of this post. IMHO, too many writers forget that they are the ones who are supposed to be doing the work, and instead they pass it off on to the player.
It is easier for the writer to simply ask the player “are you male or female.” Then the writing is simpler. But the player has to consciously set aside his disbelief, answer the question, and then try to regain immersion. It is harder on the player.
Some writers will go further: " Are you tall, short, or of medium height?". “Are you straight, gay, bi, nb, bestial, or prefer not to state?” Equipped with enough answers, it gets easy for the writer to produce a custom experience.
But the player begins to feel like they are filling out forms at Quantico, not playing a game. They are doing all the work, and are not immersed at all.
For the best player experience, the writer should do the work. It may get tricky to write not knowing how the player sees themselves, but the writer owes the player the most unobtrusive game that they can produce.
So the conscientious writer should make the player = PC, and not make the player work for his entertainment.
The more that the player can feel like they have agency, the more likely they are to stay immersed. If the parser says “I can’t let you do that”, the player begins to feel like someone else is making the decisions, and they do not enjoy it as much.
To maintain immersion, the parser should be as neutral as possible. If the game really requires that the player not do something, the parser should oppose the player within the context of the game.
For example, if the player will get killed prematurely if they go into a certain room, the parser can tell them “As you open the door, several skeletons fall out. One of them jams the door, making it difficult to open further.” If the player tries again to enter the room, the parser tells them “The door screeches like a hungry grue, and there are echoing calls from inside the room.”
The parser does not directly recommend not doing something, rather, it stays ‘in character’, decribing only what the player can see and hear, and it shows the player enough so that only a fool would proceed.