What’s to “prove”? I don’t have to prove that Twitter turned off its API after Elon bought the company, that’s a fact. I also don’t have to prove he had something to do with it, it was well-reported at the time (admittedly that isn’t quite the same level of fact, but he clearly had the influence necessary and if he didn’t agree with it he could have stopped it from happening). I believe I don’t have to prove that if Elon said Tesla should shut off its API because he didn’t like something someone built, that it would happen. He is the CEO after all.

He’s clearly one of the most impetuous CEOs in the tech industry. If you think that won’t affect people’s decision to partner with the companies he runs, well, you don’t have enough experience with these sorts of deals.