Phoronix article: https://www.phoronix.com/news/Steam-Machines-Frame-2026
Also listed here: https://store.steampowered.com/sale/hardware
Valve has already sent support for the new Steam Controller upstream: https://www.phoronix.com/news/New-Steam-Controller-SDL


Playstation definitely have the most cross platform support (and accessories) out of all of these, and solid build quality. Nintendos pro controller could have been nice if they actually cared about it, but they dont so Googles Stadia is a great standin if you can get it for cheap. I wont even talk about microshits options …