The G2 uses the OpenXR toolkit too. It should run just as well as the Quest 2 although obviously you’ll have better performance with your next PC. The G2 improves the clarity a lot, distant objects look like oatmeal in the Quest 2 and the colours/brightness are not nearly as good.
The G2 won’t replace the Quest 2 for everything, I much prefer the Quest controllers and tracking for standing, active games. But after switching to the G2 for MSFS I couldn’t go back to the Quest 2 for this sim any more.
My thoughts were that you were struggling to resist buying a PC though, and getting a G2 would allow you the treat of buying something to improve your experience without getting a PC with soon to be obsolete hardware. If you do get a top end PC you definitely won’t want to waste that peformance on a Quest 2, the G2 is much nicer.