Someone feel free to correct me if I'm wrong but Mr. X did follow you in the original B scenarios. Sure he might have more freedom to go in places he didn't before but I don't think that's indicative of any bosses in Resident Evil VII, more a result of new technology and the advancements made in gaming and programming in general.
As Mr. R already said, Mr. X only appears in scripted moments and while he does follow you, he's not actively roaming the the R.P.D Station while you're trying to solve puzzles and explore. But given how much this game does borrow from 7 in general, I wouldn't be surprised if it ended up feeling similar.