The superhero approach might (arguably) be valid in some cases -- I'm thinking of Lincoln, Washington, and FDR.

But an institution must be larger than a single person. Because if you want something to last longer than about 40 years (which is about the maximum amount of time a superhero can be super) you have to have succession.

It's also notable that those "greats" had in common a vision larger than themselves. Selflessness and an annihilation of ego, in service of a larger project, seems to be a requirement for getting yourself to that superhero status in the first place.