BEIJING—The Chinese regime’s campaign to improve conditions for workers has spurred companies, particularly some of its hardest-driving tech giants, to cut down on long hours of compulsory overtime but not all employees are happy about it. Some employees at TikTok-owner ByteDance were shocked to find their August paychecks slashed 17 percent after the company ended its policy of requiring its China-based staff to work a six-day week every second week. “My workload hasn’t actually changed,” a product manager at ByteDance told Reuters, declining to be identified given the sensitivity of the topic. “But unfortunately the salary is lower.” For the past decade, Chinese tech firms were known for “996,” a gruelling business culture that usually means work hours from 9 a.m. to 9 p.m. six days a week. But 996 was also seen as a badge of honour and was hailed as a competitive advantage over United States and European …