harlem is mostly right, that RB production is based in large part on scheme and situation... but thats not to say that running backs dont have unique attributes which allow them to perform better in similar situations
for example, compare leveon bell to trent richardson. they have comparably size/speed, but Bell was made famous for his "vision" and "patience" when running behind Pittsburgh's line. meanwhile, trent richardson had probably the worst vision/instincts of any RB in recent memory. but Bell's vision and patience mattered for -all when he ran behind the jets ty OL.
zeke does have the benefit of running behind a great line, but tbh i almost always see him fall forward. every run that looks like it should be 4 yards ends up being 6
... so there's value in that. i dont think he's a saquon-esque talent but he's probably in that second tier, along with guys like mixon, jacobs, cook, henry.
i think saquon/cmc are the most talented backs in the league. saquon is pretty generational as far as raw ability. from the 2000s, i can only really think of Peterson/LT that were in that category. maybe Chris Johnson too, for a short time