If MSFS 2020 crashes to desktop on the loading screen, there’s a high chance that Nvidia app is causing the issue. I had the same problem -(CTD on laoding screen).
After uninstalling Nvidia app and restarting PC, I was able to play without any crashes.
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Uninstall Nvidia app - not whole driver.
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@FlightCap9642 @J1mb0G5751
But, to ensure that all NVIDIA driver files and application files are completely removed, you can uninstall them using DDU (Display Driver Uninstaller). I have described how to do this in another topic – click the link below for more details.
https://forums.flightsimulator.com/t/nvidia-game-ready-driver-572-16/702204/135?u=tenpatrol
Important: After uninstalling and during the installation of the new driver, I did not install the Nvidia app. This is crucial!