Jesus, ERA echo chamber, can you be more obvious? OP isn't entirely wrong. Can you buy top of the line $1000 PC CPUs right now that are miles better than what PS5/XboxNext will have? Yes, you can. Does every PC gamer have them? No, they do not.
The situation right now is as follows:
Big majority of PC gamer CPUs right now are 4 and 2 physical cores. It will be many years before 6 and 8 cores is majority. So yes, OP is correct, PC spec fragmentation will hold games back next gen.
This actually reminds me a lot of last gen when 360 came out which destroyed average gaming PC in CPU department. There were many PC ports that received inferior version on PC as compared to 360.
So again, in the end it's AVERAGE PC spec that decides what is and isn't holding back, not the absolute top of the line 0.001% specs.