New Delhi, Aug. 30 -- Chinese investors learned a painful lesson in 2021: Beijing can tolerate a booming technology business until it decides the social costs have become too high.

Videogames were one example. Chinese authorities had worried for years about addiction among children, gradually tightening restrictions before imposing a dramatic limit in 2021: most minors could play for just one hour on Fridays, Saturdays, Sundays and public holidays. Officials said excessive gaming was harming children's study, daily lives and health.

Private tutoring offered an even harsher lesson. Beijing's "double reduction" campaign effectively dismantled much of a roughly $100 billion for-profit industry in an effort to reduce pressure on children an...