Elon Musk's one problem with owning so many companies is conflict of interest, conflicting with his role of Tesla CEO. When i invest in Tesla, i want its CEO to maximize profit for Tesla. I don't want Elon sharing AI projects between X-AI and Tesla for instance. Then he gets to decide which profitable project goes to which company. If he let more profitable project go to X-AI, as Tesla CEO, he's doing a disservice to Tesla stock holders. In fact when Elon bargained for his new pay, he exactly threatened to do AI projects in X-AI instead of Tesla.