I don't like this "McDavid was injured" narrative. For all we know he missed two games. Why did Kucherov miss one btw? Injury as well?
McDavid was beaten fair and square this season. There is no slack for "maybe" having had an injury. In fact all players play through injuries, and if you're compared to Mario as some here do, missing anything less than 10 games shouldn't matter.
To be fair the losing to Kuch (or Mackinnon) x2 and Draisaitl once in his prime, is probably what will keep McDavid away from Mario territory no matter what he does the rest of his career. (assuming he'll win a SC).
I seriously don't want to take anything away from McDavid. I think I view him in a higher regard than most posters (I think he's Gretzky/Lemieux tier). And I really do hope he gets 100 assists this year, because, as a Kucherov fan, it would be cool to see Kucherov share that accomplishement with someone of McDavid's caliber.
One thing about Kucherov, to your point, is we will likely never know if/when/or how badly he was injured. He plays a style that depends so little on his physical skills that it's just hard to tell when he's dealing with something. Especially from a statistical standpoint, because he scores either way.
For instance, you'll hear a bazillion people talking about how he could have come back way before the playoffs after his hip surgery, and then he kind of rubbed in the salt by scoring, I believe, 4 points in his return. But any TB fan will tell you, because we watch him every night: He wasn't close to 100%. You could see it in the way he moved.
Kucherov's scoring is based mainly on decision making. He does a lot of it from a dead stop.