I want to play an easy shooter where you feel like you're in a flow state aiming at targets, the only time I've ever felt like that was in the PS2 Medal of Honour, kneecap, helmet shot, head shot or up till MW4 original.
I've tried the latest CoD and the cinematics and cutscenes are just overblown.
Borderlands would be a kind of turn off your brain type but they haven't made a new game in awhile.
Helldiver had great shooting but the grind, limited levels and multiplayer means I wasn't too invested in it after a hard days work
If your looking for a shooter with a flow state, give Neon White a look. It's a FPS platformer where you pick up gun cards and you choose if you want to use the card as a gun to shoot demons, or throw it away for a movement ability (double jump, dash, etc.) as you try to get to the end of the level as fast as possible.
If the platforming and racing doesn't sound like it's for you, I saw someone else brought up Ultrakill and I wanted to recommend that as well