CEO is different from employee with no stake in the company. Sure, he probably does spend 80+ hours on his companies, but he's enjoying it. He's not beholden to any expectations of a manager. He's spending time reading/exploring/chatting and including that as 90 hours of work. Musk has no line drawn between work and play. I think Musk flaunts this public image to encourage a breakdown of work and play, not to say you should spend 90 hours checking boxes your manager gave you.