Thanks to Ed at "forums.flightsimulator.com" who solved this in 2023. It  can recur after FS2020 resets  AI to on after some FS2020 updates.

"…That sounds like exactly how my problem with the Thrustmaster Throttle started. I was getting really eratic behavior with the throttle. As I opened the Warthog throttle physically, the screen showed the throttle moving all over the place and ditto the joystick.

I finally tracked my problem down to the assisted settings. I had applied a mandatory Asobo update and this set the assisted settings to ON. This conflicted with the Thrustmaster Wathog Throttle and Joystick.

The fix that worked for me was:

Within MSFS, navigate to OPTIONS / ASSISTANCE OPTIONS / PILOTING
Turn off ‘Assisted Takeoff’
Click ‘Apply and Save’ or F11 to save your new settings

Do make sure you check these settings as they were the cause of all my issues. Even if your settings ar unset, I would be inclined to set the assited settings on, apply and save the new settings, exit FS2020 normally, then go back in and reset the assisted settings to off, then apply and save again. Then exit FS2020 and reboot your PC and then start your PC and go back in to FS2020 and try a take off and see how things go.

I’ll keep my fingers crossed that all works out well for you.

All the best

Ed"