Nothing? All of chapter 4 and 5 have been added since '2 years ago'. That's the basketball game, almost all of getting to know Zara, the tabletop, the locker room, the dinner with Nick, Vanessa, the tennis game, the morning with Bella, the visit to Nia, More bella, the book club, Katie...
So, really, not nothing that wasn't there, but there's nothing you're interested in. I'll admit, the tabletop made me sleepy...
Not disagreeing with your logic, but the rating was 16+ for the German market that he was aiming for, not 13+US German's have different ratings, as does Europe, as does Asia. Ocean wasn't trying to get it for teens, he was trying to avoid 18+ for geoblocking reasons, because Steam. But it is a dead horse, that bolted the gate, and then got locked up and ...yeah, all that.
Well, you got me at Katie 100% correct