Gates was famously so, at least when he was leading MSFT. Ballmer, moreso. Ellison is a well known asshole. Etc.
It's especially true of founders, I reckon, because through grit and luck they find themselves atop a large heap of money and power, and it's very easy to forget how much of their success was due to luck -- and very easy to believe that it was all due to how exceptional and smart and visionary they were, or whatever.
So, yeah, probably a dick. Probably not somebody with a lot of close friends. I mean, would YOU be friends with a guy who was denying his own child like that?
From the Economist: "While [Elon Musk danced] with his first wife on their wedding day, he told her, “I am the alpha in this relationship.” [1]
[1] https://www.economist.com/business-books-quarterly/2015/07/0...