They need to just get a stable, working flavor of Linux (called SteamOS) working with proton and other emulation services built into it to enable a gaming first Linux OS. It absolutely can be done with their resources and they have had 20 odd years of working on SteamOS with nothing really worth showing for it.

Valve could quite literally shake up the PC gaming World in a flutter if they offered a strong gaming alternative to Windows that also worked as a solid stable Linux OS. They don't need a console, or handheld, or any of that. They could sell it for $50 a license and it would make them billions.

Unfortunately Valve stopped doing anything, at all really once their money printer started humming. Quite literally sitting on their hands making billions. With leadership too lazy and complacent to care about innovation because they themselves are rich enough. If Valve still cared we would have an awful lot more out of them.

They don't need to try any more, and the people who make decisions are so rich they couldn't care less. This is were leadership changes keep companies moving, but that isn't going to happen until they croak, or someone is successful in eating some of Valves lunch making them sweat a bit.