Before diving into settings, check whether the controller’s actually drifting or if Battlefield’s just possessed.
Go to https://gamepad-tester.com/
in your browser with the controller plugged in. Move the sticks around and see if the left one keeps registering input when centered. If it does, that’s hardware drift. If it stays still, the game’s input polling is drunk again.
If it’s the latter, launch the game with only one controller plugged in, and in Steam (or EA app if you’re cursed enough to use that one directly) disable Xbox Configuration Support. Battlefield sometimes double-binds inputs like it’s trying to remix your aim.
If nothing fixes it, congrats — you’ve rediscovered Battlefield’s “immersion by frustration” design philosophy.