Tech mogul calls director Alex Gibney a ‘bitter old man’ who has ‘zero integrity’ in series of posts on XElon Musk has issued an angry tirade at the film-maker behind a four-hour documentary about his life and influence, labelling the director Alex Gibney a “bitter old man” who has “zero integrity”.Gibney, who has previously made films about the collapse of Enron, WikiLeaks and Vladimir Putin, premiered his Musk documentary at the Venice film festival this week. He said he believ