I'm with ErHaO, I can't see GamePass or PSNow (or PSPlus) moving to a situation where they have new AAA titles on them. I could see it following TV & film streaming services, where the big budget releases in particular come out in the cinema first and then arrive on subscription services (TV and/or streaming) 6-12 months later, and then they mostly don't stay on permanently.
But I have to say, having these subscription services for older/smaller games we might have missed is a cool development.
Also completely unrelated but I finished Final Fantasy VII Remake last night. I like it, but the final chapter was really weird. I was loving it up to that point, but the shift in focus and new concepts were too rushed IMO. At this point in the original game, they hadn't revealed much more yet as from memory that happens when they get to Kalm, but Cloud wanting to go after Sephiroth and the others supporting him felt reasonably natural, whereas in the Remake there are these huge stakes that seem to have come out of nowhere unless you played the original game and know what happens. Which I did, but I still think it makes this narratively weak - a Remake should be able to stand on its own.
Now that they've given themselves greater licence to change the story going forward, there is also an understandable worry that they'll just do something completely different where it was the post-Midgar story in the original that was so special. So I really hope they keep the narrative largely in tact, and I suppose there's also an opportunity to take out some of the fluff and make it more coherent. So the weak final chapter in Remake is definitely recoverable if they do it right. Just a shame to have ended up a bit of a bum note.