↓↓↓↓ POSSIBLE SOLUTION FOR JOYSTICK NOT BEING DETECTED IN ARMA3 ↓↓↓↓
I was experiencing an issue where my new Thrustmaster Warthog HOTAS was not being detected by Arma3 in the Controls > Controller window.
I eventually fixed the issue, which I tracked down to the following Steam Controller Setting: Steam > Settings > Controller > General Controller Settings > Generic Gamepad Configuration Support <--Switch this OFF
After I changed this setting, I restarted Arma3 and my Joystick and Throttle appeared as detected in the Controls > Controller window.
After binding the controls, my joystick and throttle worked perfectly.
If you're having the same issue, I hope this solves it for you, good luck!
o7