> Barring them from leaving the country feels a bit sinister for people who haven't been accused of committing any crimes

I don't think it's actually that uncommon in China, especially with high profile people. To China's credit, we often bar people from leaving the country if they're charged with a crime but not convicted of anything. While it's certainly scary and authoritarian, I think it's par for the course in China. Most companies have some amount of CCP representation in them, either on the board or some level of management.