Not long after news first emerged three years ago that Alex Gibney had begun work on an in-depth study of Elon Musk, the uber-tech bro went on the defensive on his social media platform, Twitter. Sorry, I mean X. “It’s a hit piece,” he cried, before switching to the totally mature “Gibney is a douche.” It must have been no surprise to the filmmaker that his subject would decline to make himself available for Musk, a whopping documentary think piece running close to four hours, which traces in dense detail the dizzying ascent to stratospheric wealth and influence of the man...