All the billionaires are mentally ill. It's not a natural human condition, and clearly leads in most cases to monomania, megalomania and some degree of sociopathy. They come to believe the size of their bank accounts makes them into gods.
It's why I think we should ban the concept entirely. After the first $100 million, maybe adjusted every ten years for inflation, you don't get anything more. Sure, maybe you don't become the big innovator, but honestly, a good deal of the time after the initial invention (if they actually invented anything at all, which with Zuckerberg is debatable), it normally ends up in some sort of Edison's lab scenario, where the big rich "inventor" is paying actual researchers to create things that the big rich "inventor" can claim as their own.
In the ultra wealthy simply become enablers of tyrants. Think Crassus in the First Triumvirate, an equal on paper, but in reality a background figure whose wealth served Caesar and Pompey the Great more than it ever served Crassus himself.