He is an outlier, nobody is disputing that. Regardless of the odds to end up a multi-billionaire from a wealthy background, the odds of doing that from the working class are much lower. It does not mean that it never happens, I am sure there are examples.

> I'm also pretty sure with his first company sale he made much more money than his family ever had to begin with.

Well yeah. But he got there partly because he had some money to invest in the first place, and partly because he had useful connexions.