This kind of thinking is what Mitch Kapor calls a "Mirrortocracy". It can work, in the sense that maybe you can recruit enough people just like you, down to quirks of phrasing, and succeed in your mission. There are advantages to belonging to a cohort. It is the reason why people in the military wear uniforms and go through bootcamp.
But categorically stating that diversity is wrong is, well, typical of the provincial attitude that caused Levchin to run his companies the way he did.
But just because he's rich doesn't mean he's right.