There's still a significant amount of people who buy consoles for their exclusive games. It's been the model for a reason. I certainly wouldn't have gotten a PS5 if it weren't for it's exclusives, and thus I would have also never purchased any of the third party games that I have. Sony gets a tiny cut for each and every one of those third party sales and that's the real money maker for console makers, and it's gone if I'm instead just purchasing everything on Steam. This isn't even mentioning Nintendo, who has the most exclusives and has vastly outsold the competition largely on the backs of their exclusive games.
Mr It's not the same lol, a PS5 exclusive just won GOTY last month. It should have more exclusives but it still has a handful compared to Xbox's zero exclusives.