Perhaps it's just me, but in the Zuckerberg case specifically, I'd think quite a bit of luck and timing had to do with it. If Zuckerberg had been born 10 years later after the obvious social network ideas were already created? Or if he had gone to a no-name college (or none whatsoever) and Facebook had never taken off the way it did at Harvard?
Or maybe you meant they were born elite, in which case, I don't know anything about that.