Well ain’t that just the question!
So in the community video today they made a lot of the fact they are upgrading to DX12 for the features it can bring... one could perhaps infer that some of those features could be VRS, mesh shading, sampler feedback (which is a potential huge win for VR where you can render all the pixels in a scene once and just reproject to the other eye, much like Nvidia’s SPS but not vendor specific), perhaps even direct ML based upsampling... there was a very cheeky silence when DLSS was mentioned - probably just a co-incidence that the beta is slated to land around the same time as AMD's RDNA2 presentation, but not impossible they are keeping certain things like that under their hat until then.
They are also apparently working on continuing to move jobs off the main thread which would help remove a lot of the CPU bottlenecking we are seeing.
While they definitely didn’t say so in clear terms, maybe one could speculate that the VR update is waiting upon the DX12 conversion (which they say they’ve been working on for a while already) to take advantage of some of those advanced DX12 ultimate features to help make it more playable in VR, along with just continuing optimisation with more jobs being moved off the main thread in the next update. Probably wishful thinking and it'll just be a pig to run but one can dream.
There is also of course the back up option of reprojection/motion smoothing which is more bearable in a flight sim, so you’d only need to hit eg 45fps for a 90hz display or you could perhaps use the 60hz mode on WMR.
If not then dialling back the options and buying a BFGPU as Jensen would put it