Valve continues developing Proton, which is the layer of software that allows Windows games to run on non-Windows operating systems. And it seems they're in it for the long-haul, because they are putting developers to work on Wayland support, which may point to plans for the Steamdeck 2 running on Wayland by default.

Though, xWayland will be doing the grunt work there for some time yet in Proton.