Nobody else was pushing reusability in the way Musk was, or with the same approach of propulsive landing. Pretty much the whole rest of the industry was absolutely convinced it was impossible. Yes he found a few engineers willing to try to make it work, but without him going all-in on it from the top there is no way we would have propulsively landing first stage boosters today, and maybe not for many decades to come.

That doesn't make Musk perfect, he may well have many negative personality traits that get in the way of progress on other fronts. On Starship as well though, plenty of engineers there confirm that it was Musk that came up with the idea to switch to Steel as the primary structural material.

It may be true that if you take one 'great man' out of the picture we might still get the same innovations, but in some areas like space rockets it's not something anyone can knock up in their garage to matter how bright they are. There's also the argument that ok, any one great man might be replaceable, but often I think you'd find them replaced by another great man. Some big leaps forward take a lot of capabilities in one package to make them work, or occasionally in a great synergistic partnership such as Jobs and Wozniak, or Lennon and McCartney.