While both side are impressive, I think the risk is really the big story. Of those people worth at least tens of millions, how many would be willing to risk their entire fortune on a venture that, in their honest assessment, would probably fail? (There's a quote somewhere, where Musk actually says he expected SpaceX to fail, but did it anyway because of how great it could be if it succeeded.)

I bet the number is pretty damn small. A big part of how he got to this point is simply the fact that almost no one else would have been willing to try. Beyond that, he must have been extremely skillful and lucky to actually succeed.