> Does anyone say "we don't know if Einstein could do this because we were really close or because he was really smart?

Yes. It is certainly a question if Einstein is one of the smartest guy ever lived or all of his discoveries were already in the Zeitgeist, and would have been discovered by someone else in ~5 years.

Both can be true?

Einstein was smart and put several disjointed things together. It's amazing that one person could do so much, from explaining the Brownian motion to explaining the photoeffect.

But I think that all these would have happened within _years_ anyway.