I got confused because the title of the thread is different than the poll question.
the most important person in the superhero genre IMO is Richard Donner, because without that groundwork, it's hard to imagine how things would progress.
As for "who saved the superhero genre" which is a very different question, that would be Kevin Feige. He changed the game. No one would be doing these massive universe building films if it weren't for him. He was openly scoffed by people at Fox and WB for trying to do that, and when Avengers became the huge success that it was, people took notice.