You speak as if Elon Musk didn't buy tons of AI chips for full self driving (Dojo) and COMPLETELY flub it.
It's the same as always. Musk himself is an awful business man. He relies upon buying the success of others and taking over. Outside of that, he's kind of awful. Initiatives started by Musk himself almost inevitably fail.
10 years returns S&P 500 (index of all those better than Musk): 261% Tesla: 2700%
Disclaimer: My portfolio is 65% Tesla.
I absolute abhor the man but I think this is silly. No doubt that he has had luck and help, but he is still a good businessman. He's certainly an asshole (almost certainly dark triad territory), but I think that can be a benefit when creating a business.
Tesla wasn't "successful" before he "took it over" (read: invested most of their seed capital and ran the actual day-to-day operations).
SpaceX, founded entirely by him alone, is also the most valuable space technology company on earth, so...