Yes for roughly 30% more frames.
And it was the gpu, SU5 brings no fps improvements to VR (but more smoothness). With the 3090 I get very fluid 30-35 fps everywhere. With my 2080ti they where between 20 and 30 fps with an huge impact of what aircraft you use.
The interesting thing for me is that the fps seemed to be somewhat capped/equalized as they are almost the same now somewhere nowhere or in hd photogrammetry areas and also independent of what aircraft I use.
I rate this positive as it free you from thinking to fly what and where.
No for Vram at the moment as Vram usage is massively reduced to make it work on the xbox. I do actually dont go over 12gb anymore with G2 at full resolution so an 3080ti will do almost as well as an 3090 without the option to fry eggs at the backplate.
It is definately an insane investment for 9 or 10 fps more but for me it was worth it because 35fps feel so much better.
Fps noted above are measured with oxr100/rr100/TAA/G2 Tlod 200, Olod120 medium/high settings mix.
By reducing oxr to 80 you can gain another 10% fps at the cost of slightly more softened terrain textures what does not make a big difference now as they are already softened by default to reduce the Vram usage. So you only can choose between soft and a little softer.