Since I have a threadripper and a Titan RTX, I maxed out graphics settings, mwahahahahahaha cough cough, hahahahaha, etc etc....

Anyway, It is a statistical fact that Steam Input totally screws up gamepad support on 99.8% of all games it is used with.

Switching steam input off on Linux revealed the underlying issues, steam input was mapping input controls to keyboard+mouse which obviously doesn't work on a dvorak-mapped keyboard. Once again, steam input is always completely broken with maybe one or two exceptions in my entire library. With steam input disabled, the oddest symptoms emerged,

1. Non-axis buttons were working fine. The game was reacting to buttons such as jump, crouch, etc.

2. Even though the game was responsive to the controller, it was ignoring the main axes, both sticks were dead.

The settings menu implied that gamepad should be supported by the game, which makes it deeply puzzling as to why the game was not reading the gamepad axis input.

Only other issue is that during load-up the game tends to crash if you re-size the game window.