If I were building a new system I would focus on spending less on PCI-E v5 compatible MB and gen 5 nvme and instead spend it on a faster CPU. A faster CPU (single thread speed) is something you can take advantage with VaM, no doubt. Those who use a lot of AI or plan to focus more on GPU VRAM.
If you also intend to copy a lot of files around, perhaps a gen 5 premium may be worthwhile, depends on your usecase. VaM wise I don't think it would matter much compared to other HW choices, but would be cool to have numbers and experiences from gen 5 owners for real comparisons.