After selling to facebook he got flack. And then became an open supporter of Trump. He became hated.
My guess is that he's a narcissist similar to Elon Musk, so him hearing himself called a looser and asshole (like he is) triggers him to be worse. To go "I'll show him". To do a nazi salute or you know, engineer dogs for war to oppress people more efficiently. Any supporter of Trump is obviously a psycho with no moral center, but if they also have narcissism and money and power, well it can get much worse.