I used to be a console gamer. Bo2 on the Xbox 360 was my favorite game of all time. I moved to csgo, once I got a pc.
My gripe with fps games on the deck is it doesn’t feel like a console fps, it feels like a pc game. I obviously understand why but I wish I could think of a way to change that. The controls just feel awful to me
Weak/no auto aim? Depends on the game you're playing, but I imagine CSGO doesn't have any. Maybe you could find a different shooter that accommodates joystick use?
I have to imagine that this is an aim-assistance scenario. CS does not have aim-assist in order to prevent abuse by M&K players. Most other games have toggles in the settings for contrller use.
You could always try one of the more precise deck aiming schemes like flick-stick+gyro.
COD doesn't work on Linux, unfortunately. So no steam deck support either. Same with Destiny 2, which has imo is best feeling gunplay in any game I have ever played.