Hmmm…very odd. Just as a test I set the Piloting option to Hard (as you did), chose the 172 G1000 plane and while sitting on the runway, all Flight Assistant settings were turned off. I then went back to Main Menu and set the 3 AI settings in the Piloting section to ON. Back on the runway with the same plane and only those settings were turned on.
Back to Main Menu, switched to the DA62, back to the runway and the Flight Assist setting had not changed. As a final test, jumped back to Main Menu, set Piloting section to Hard again, back to the runway (still with the DA62) and all the Flight Assistant settings were turned off.
It is just amazing to me that even the most mundane things in MSFS (like difficulty settings in options) can be different between machines. Perhaps it is an issue with PC vs XBOX versions (I’m running on a PC).
Hope you can find a way to make it work. Having to constantly reset settings (like drone speed) is a real pain.
–Ron