Well the 8bitdo controller has 3 modes you can use: Xinput (Xbox, the standard on PC), Dinput (Playstation) and Switch. Some features are only available in the other modes, because Xinput does not support gyro. So you can use gyro only in Dinput or Switch mode. Same for Switch, it does not support analog triggers. I think there are differences in Bluetooth vs 2.4 dongle, but I don't know what it is.
So if you are like me and use the 8bitdo (or watched others reviews) in Xinput only, then you can't use gyro and this has nothing to do with Steam Input support; it's the controller firmware itself.
The reason why I don't want to use the other modes is, because I have to enable them by holding button when turning on the controller. But the stupid 8bitdo firmware does not accept changing the mode when taking it up from the dock. So I would need to take it, turn controller off, then on with button... this is so inconvenient for daily use. Normally the state of last mode would be saved in the controller, but when taking it up from the dock its always Xinput as I understand.