That’s pretty debatable imo. Howe only peaked higher if you ignore games played for Lemieux, and don’t make any kind of era adjustment for his 4 peak years happening in an all Canadian league in a relatively weak post war environment. The fact that Howe wasn’t close to that dominance after those 4 years suggests this might be the case as well since Lemieux was at that level much longer.
But even if Howe is seen as number 2, I don’t see how how McDavid can’t pass him either considering he already has 2 seasons that are pretty comparable to Howe’s 4 peak years, so far has been just as if not more consistent and was elite from a younger age. He already has more Art Ross trophies and more Harts than Howe at the same age and will probably lead the playoffs in scoring by two times by 27, same as Howe. If he can have another 2-3 years at his ‘21/‘23 level, which wouldn’t be unusual considering he was at nearly 2 points per game again after his injury start, stay healthy and age well, he could definitely make a case. Though I doubt he could ever get to a point where it’s consensus