These controllers were all working on SteamOS before as far as I know, so I’m interested to see what this changes. My understanding is that previously their controllers just show up as generic xbox controllers, and now they will be properly recognized. We’ll see if this has any other benefits like custom bindings for back buttons and things like that.
I have a Pro 2 too and switched from Xinput to Dinput at the back of the controller and my Steam Deck now identifies the back buttons like L4/R4 (but with the name PL/PR) and I can map it to anything I want