They have already slow motion done this with the major apps in AOSP. Go look at the SMS app, for example. Google doesn't owe us anything, so not a criticism. Just an observation. It isn't a leap to imagine that they may do this with the OS at some point. 

 The main incentive I can see for them to keep Android open is that it's open, while the alternative isn't. If I had to choose between iOS and stock Android on a Pixel, I'd probably choose Apple. For context, I'm a hardcore GrapheneOS/AOSP maxi and have been since Android was created. 

 In reality, I'd actually just go back to a dumb phone or some Gnu/Linux phone, but I mean IF I wasn't willing to do that or it wasn't an option. 

 Chances are that's what I do. When I can get my own place again I'm going to have a "landline", a phone table, and an answering machine. Current social pressures already make this difficult. Most of my friends chat on different apps all day so I'm isolated from group chats, events and whatnot. So if we want to catch up or do something we need to schedule a call. So I don't often get invited to small things