I think from 2011-14 was really when we could have seen something like what current McDavid is doing in terms of peer dominance, he was absolutely ripping up the league in 2011, had the highest ppg in the league by far the next 2 years after, and then won the AR the next year he was healthy by 17 pts over 2nd place.
I truly believe he would have won 4 straight and likely by a very far margin, he had a ppg of 1.47 over that 4 year span while next was 1.2 and that was Malkin, Stammer was 1.14 and then St louis/Giroux sat at 4th and 5th place with a 1.05 ppg over that span. Obviously availability is the best ability, but in terms of how much better he was when he was healthy than the other top 5 players in the world is very similar to that of McDavid now.
For example Crosby's ppg was 22.5% higher than 2nd place, 29% better than 3rd, and 40% better than 4th/5th over that span.
Over the last 4 years McDavid (1.7) has a gap of 15% on Draisaitl (1.48), 22% on MacKinnon (1.39), 25% on Kucherov, and 33% on Panarin (1.28).
Again, what McDavid is doing is absolutely absurd and his abillty to stay healthier is definitely impressive, but Crosby was absolutely capable of having that sort of statistical dominance vs his peers in the prime of his career. It is kind of a shame he will only end up with 2 scoring titles and MVPs as he was the heavy, heavy favorite to win every year from 2011-14 had he been healthy.