From someone who built his own rig, circa 4k+ spenton it so far, mostly on water coling and blocks, I can run MSFS on ultra with no issues. Elite (not shootymacshootface) runs andf barely taxes the system even with VR. The real question in picking, buying, building, a PC is future proofing. Elite isn't the only kid on the blcok or SDD so you need tomindful of what is coming down the road in terms of tech and companies using that tech. In fairness the last year has been a pain on the GFX card front so, sticking with tried and trusted for now is perfectly acceptable.
I would never build a rig just for one game, and even if I did, Elite would hardly be a contender. It's fantastic in VR, meh in everything else. Can't speak for oddysey as I didn't buy into the hype. (so glad)