Continuing the discussion from Getting out of VR with Ctrl-Tab causes CTD (Reverb G2):
Last version from NVidia, I downloaded it while updating the sim

I can also confirm that SteamVR is not loading, it loads through WMR.
The funny thing is that I can swith while in the main menu, into VR, and back, as many times I want. …but…but…but… try this.
Stay in 2D, Load a flight (the plane will position where your flight starts…) then try to change to VR. It does not allow
Thanks @DerKlausi