Survivorship bias. My own experience is that the jerks self-select out because no one wants to work for them.

That said, in the entrepreneurial space it's less clear to me this is true. In a team setting? Sure. But the C-suite of a business isn't necessarily a team sport and a lot of wildly successful CEOs are notoriously pieces of shit including Gates, Bezos, Zuck, Musk, and many others.