It does seem that way, but if it's possible to run SteamOS on some sort of custom Linux box, if not a normal Linux PC, for me at least that would be good enough

It does seem that way, but if it's possible to run SteamOS on some sort of custom Linux box, if not a normal Linux PC, for me at least that would be good enough (that way you can enjoy the latest graphics hardware, which is the main draw of PC gaming along with mods).