What would an official steamOS desktop do that bazzite can’t? Unless you need commercial support because you are selling steam machines I don’t see how a official release would be of advantage.
I think there’s just people that trust Valve more than Linux in general.
SteamOS on the deck is extremely foolproof, and people who are otherwise scared of Linux seem to think SteamOS magically fixes every perceived issue with desktop Linux.
That’s my best guess but I’m just some dude.
My brother plays games on Windows. I tried to convert him to Linux like two times, but he doesn’t want to do it. He doesn’t even play multiplayer games. Just single-player and co-op games. So Anticheat wouldn’t be a problem. When I said to him that Steam is releasing their own Linux distro, he said: Sure, I will try that.
That was almost 3 years ago and there still isn’t official steamos for desktop.