So I think I found the issue. For PC, the easy fix is to actually turn down your desktop mouse sensitivity. The game currently has no control setting to turn down mouse sensitivity specifically, so those with high dpi mouse will be affected a lot. Note you can turn down freelook speed in the camera options in msfs but that turns down the sensitivity for all controls.
What MSFS needs to do is to recognize the mouse is different than a controller and implement the normal game sensitivity controls that we are all used too.
I also think this would require more time than a simple patch that people are expecting. Also as of now all camera sensitivity options are controlled by the camera options and that is wrong as all camera settings sensitivity are applied globally and not specifically to hardware.