Seriously, if you're a celeb over there and caught smoking a joint, your career is basically over.
Even the infamously prudish U.S. is more accepting of it.
I'm guessing it's a leftover of U.S, imperialism, like how all their porn is still censored.
East Asian countries generally have strict drug laws. You could attribute it to Confucian values (with drug use being an individual act that is harmful to the community)* or to the legacy of the opium wars, where a foreign power forced the drug laws of China to be lenient in order to flood the country with drugs.
*attributing cultural differences between the west and Asia to Confucianism is a little orientalist sometimes imo
I agree about overstating Confucianism, which doesn't explain how 1/3 of China could get addicted to opium if it's such an "individualistic" thing.
It's 100% the legacy of the opium wars. Funny thing though, Chinese culture doesn't care nearly as much about weed as South Korea, Japan, or Singapore. Marijuana grows wild in southwest China and little old ladies will often sell it in on the side of the road in places popular with foreign tourists.