I should have included this but yes, there is a whole court case about this: https://corpgov.law.harvard.edu/2018/04/23/elon-musk-and-the-control-of-tesla/

But he doesn’t own Tesla. I was mainly trying to focus on that point.

Though as others have mentioned he gets his wealth from many other sources. Small sourceless point but capital accumulation rarely occurs from ownership in a single company.