tl'dr: The game is rigged for the top 1% so it can face less competition and not allow some of the money it gains to flow downwards.
The concern is more that their children, and their children's children, are likely to be in the 1% as well, no matter what they do, or don't do.
http://time.com/money/3925308/rich-families-lose-wealth/
It is a very known fact, but I couldn't find better sources quickly, so this article has to do.
I'll add that they also are all Americans, 5% of the world's population with an enormous advantage. Based on the success rate of tech startups in Somalia, I would guess that if they were born there we never would have heard of them. How many brilliant people does the world lose to bad circumstances like that? Almost certainly, it's nearly all of them.