Look, I understand what OP is trying to say.
If we rate the level of competition in the NHL on a rate of 1 to 10, it was probably ~4 during the Howe-era. Everyone knew, that some of the guys just weren't that fast, or skilled for that matter. So Howe dominating that era wasn't as impressing, as if the competition level was higher.
Then comes Gretzky and his peers. Everyone seems to be a little more skilled, hockey as a sport is growing and it takes even more effort to make it to the big leagues. But still, there are fellas like McSorley who just... are not that good.
Years go by and comes the era of McDavid. There are no goons. There are no slow skaters. Teams roll four highly skilled lines. You have to be extremely gifted to make it even as a bottom-6 player. I've played pond hockey with some of the worst players of 2010's NHL and time after time they wrecked our squad. Competition level is higher than ever.
What happens, when we hit the ceiling? What happens when you can't claim a spot in the lineup, if you don't have high hockey iq and can't skate fast, shoot hard, kill penalties, etc. If everyone needs to be as good as humanly possible... well, think about it like this: EA Sports NHL, but every player is rated 99 overall. When everyone is the best player of his generation, no one is. This is the day when we can't no longer put one player above the other.
Fortunately, we will definitely see dominant players in the future. Logan Shaw is not going to be the last Logan Shaw we see in this league. At the end of the day, it all comes down to money. You'd rather take a chance on some minor league scrub making $700K than bring back Markov with $4M deal, even though Markov is better. And the talent pool just isn't that deep. There will always be relatively bad players in every team.