If Xbox becomes a branded PC, it won't matter whether or not it can play Sony's PC ports. It'll pose as little threat as a SteamMachine or SteamDeck, so it's not something Sony should worry about. But Xbox fanboys like ColtEastwood and Jez Corden will celebrate like it's the end of Playstation and act like the cunning and ultra smart Microsoft revolutionized gaming.
Sony's core problem here is the idea of bringing their games to PC, which the next Xbox will be a very small part of. Their PC program should slowly make PS platforms redundant, and it already caused a lot of damage in the internet discourse. Sony probably wouldn't mind becoming a closed PC under one condition: having their entire store and playerbase from consoles preserved (but even then, they wouldn't be able to keep multiplayer behind a paywall anymore). This is pretty much impossible. Even if they somehow pull it off, they would be losing more players to Steam than gaining. Steam is too powerful and could slowly kill Playstation on PC, or render it tiny.
I'm actually a little surprised MS isn't trying to get Steam or convince Valve to sell. It's the only sure way to dominate PC.
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