They’re probably building off Windows RT (the locked down variant designed for ARM tablets).
If they were smart they’d imitate some of how SteamOS runs games in a modified WinRT environment - TLDR do NOT start up the entire Win32 runtime and desktop environment by default, don’t run stuff like printer services and whatnot, just run a simplified sandbox and window manager with just the APIs needed to run the games similar to Proton. Then let the user switch to desktop mode as needed, but don’t run it when gaming.
They’re probably building off Windows RT (the locked down variant designed for ARM tablets).
If they were smart they’d imitate some of how SteamOS runs games in a modified WinRT environment - TLDR do NOT start up the entire Win32 runtime and desktop environment by default, don’t run stuff like printer services and whatnot, just run a simplified sandbox and window manager with just the APIs needed to run the games similar to Proton. Then let the user switch to desktop mode as needed, but don’t run it when gaming.
I’m guessing this is basically how the Xbox works already.
It’s not so much Win32 though on Xbox, the biggest similarity is the x86 CPU and the shared kernel and some security stuff
Edit: forgot the obvious, DirectX