Hi, hope the following helps you, and anyone else with similar specs. Mine are:
i7-7700k, overclocked to 4.8
Nvidia 1080Ti
32gb DDR 3000 RAM
Oculus Rift S
MSFS through Microsoft Store (not Steam)
First,you need to folow Nomagno’s advice about the Registry edit. Make a backup of your Registry first, in case things go wrong!
Suggest you also switch to the Oculus Beta within Oculus.
In terms of settings, I’ve played around a lot over the last 5 days, and these seem to work best for me:
Suggest you download and install the OpenXR Developer Tools from the link given at:
In the Developer settings, set:
Use latest preview OpenXR runtime - on
Custom Render Scale - ticked on, and at 100%
Motion Reprojection - always on
Download Oculus Tray Tool (if you don’t already have it), and change the following settings:
Default Super Sampling - 1.3
Default ASW Mode - 30Hz (this is important for stutter-free play)
Adaptive GPU Scaling - Off (this works better for me than on)
Keep Oculus Tray Tool running while in MSFS. You can set the Visual HUD to ‘Performance’ if you want to see the fps in VR. With these settings and hardware it should give about 27.5 fps.
In terms of in game graphics settings, these give me an acceptable trade-off between performance and graphics:
Is it perfect…?..No, and I doubt it will be without much more Asobo optimisation. Is it fun…? Hell yes!! With these settings, I’m pretty much smooth and stutter free with GA steam gague aircraft in non-intensive environments… but that’s all I fly right now, as the airliners need a lot of work. It may struggle in densely built up areas, though, or with custom scenery ripped straight from Google Earth without being optimised, but we can’t have everything… I’m looking forward to being able to get my hands on a 3080 and crank some settings up! 
In the meantime, if you struggle with these settings (but you shouldn’t with your specs), you can have a look at the post below, and dial back in game on some of the biggest fps killers.