I believe a couple of things happened over the last few years that basically broke him. One factor may have been his daughter coming out as trans, and I have a feeling that another factor was a realization that his ambition to start a Mars colony wasn't going to be possible in his lifetime. Being forced to give up a major life goal hurts deeply no matter how much money or influence you have.
He started engaging in irrational, erratic behavior circa 2019-2020, such as getting into the pissing match with Unsworth, offering and then being being forced to overpay for Twitter, and pivoting towards full-blown Trumpism and neo-Nazi-adjacent politics. Before then he was just known as a hard-driving Bill Gates-style nerd CEO. By now, I don't think he cares about any role except that of cult leader.
2. Why traders continue to buy Tesla stock even as sales nose-dive.
See above. It's not a car company. It's a robot company^W^WAI company^W^Wenergy company^W^Wtaxi company^W^W personality cult.