I think most Bitsy games could actually be transformed into “proper IF” very easily, for example in Twine. (Making them parser games would be overkill.) The only reason they wouldn’t be playable if you removed all the graphics is that you’d have to add some textual exposition to replace them, not necessarily that the experience would be drastically different if that’s done. In fact, maybe I should try to do that with my Bitsy game!
Interestingly, this thread is starting to overlap with this one now: RECOMMENDATION REQUEST: The Future of Interactive Fiction - #50 by ChristopherDrum