SteamOS already runs Linux desktop, at least on the steamdeck (it's just "switch to desktop" in the power menu). The default desktop environment is KDE plasma. Paired with a USBC laptop dock, you have an easily switchable desktop experience too.
Hopefully they don't plan to change this!
No worries! I agree it's a killer feature - hoping to pass the word along. Sorry if it came off as a correction, I meant it more as a "wait til you hear this too!"