I saw a pretty convincing argument that Musk fried his brain with ketamine, written by a former ketamine abuser who saw a lot of familiar behavior. I don't think Musk is the same guy now that he was in the early days.
I found the article I was talking about: https://alisoncrosthwait.substack.com/p/a-ketamine-addicts-p...
It says it's quite easy for ketamine use to get out of control without the users noticing, that they're are able to work effectively despite that, and that they tend to develop radically different and delusional beliefs. Given that Elon has admitted to self-administering ketamine, I don't think the idea should be dismissed.