Last Sunday, Elon Musk posted a poll on his new toy, Twitter, leaving his future as the platform’s CEO in the hands of its users. “Should I step down as head of Twitter?” he wrote. “I will abide by the results of this poll.” In retrospect, it might just be one of the billionaire’s less prudent decisions (and this is a man who named his kid X Æ A-Xii). With over 17.5 million votes cast, some 57.5% of respondents decided that the 51-year-old SpaceX founder shouldn’t stay on as the site’s boss, doubtless denting an ego so gargantuan that, ironically,...