Valve appear to have some pretty ambitious future plans for Steam, as we've seen recently a leak (and not for the first time) that Valve has plans for ARM64 and Android support on Linux.
ANDROID??? can we play Triple AAA games on android that would be soo fire
You have it the wrong way around. It's about Android games on SteamOS. Oculus/Quest runs a variant of Android, it just makes sense to have a Proton-style porting aid for Quest games on SteamOS.