When a young female employee at Alibaba, one of China’s biggest technology firms, accused her manager and a company client of sexually assaulting her after an alcohol-fueled work dinner last summer, it seemed like a turning point for the country’s fledgling #MeToo movement. Months later, it had not played out that way. In September, prosecutors decided not to charge the woman’s boss because, they said, his behavior did not constitute a crime. In November, Alibaba fired the woman, who has been identified by the police and her lawyers only by her surname, Zhou. The company claimed Ms. Zhou had damaged...