Touchpad always works, but the haptic triggers and rumble need you to be wired. They also only work in supported games like Spiderman. I remember needing to go into desktop mode to enable the controller’s “speaker” for the rumble.

Adaptive triggers begin as a hardware feature. Steam Deck can’t emulate that without changing the triggers out completely (if it’s possible at all).

I imagine the internal motors for the crazy precise haptic feedback is also hardware level.