Well, he is so out of depth regarding engineering a car/rockets that the only thing he can possibly do is to hire some smart guys who work for him. He literally only has a single patent for tesla, a goddamn door handle. (Oh, also, they are feeding on government subsidies)
Twitter is a much different category where you “only” have to manage people, there is no one stopping his narcissistic personality from doing harm and here is the result. Why do you give him the benefit of doubt? It could have easily been a CEO-swap without any worry from the outside. But he posted controversial shit instantly, made up a ridiculously stupid paid-verification which removed the trust from accounts, fired plenty of its talent base wrongfully! having to rehire many of them at presumably insane costs, while also don’t forget about severance. He is just terribly incompetent at his job, if that is anything more than being an ATM machine.