It does break a few things, but they aren't really things worth going into. Tony and Bruce didn't know each other prior to being superheroes, until they went into Heroes Reborn and remembered being pre-super friends there. Like, it was a specific plot point when they came back that they remembered being buddies, and also not. But as retcons go, I'm totally fine with this one. Blame it on the time quakes in Age of Ultron or whatever.