To be fair, having a lot of money is an excellent way to have more money. Having a lot of money and making some lucky gambles in early technology plays is an even better way to have a lot of money. The fact that every company he owns a significant stake in has a 'manage Elon so that everyone else can get things done' team except for twitter and all of them are not doing insane things, except for twitter, seems to be a pretty strong indication that other enterprises he's involved in are not succeeding because of him, but in spite of him.