Doesnt tiktok have a personalized feed for China that promotes healthy habits and everywhere else it's more likely to morph into brain dead content spirale?

TikTok is banned in China

That remains unproven:

"TikTok has never been available in China, as the country has its own version of the app, called Douyin. Both apps are owned by the same Chinese company, ByteDance. Thus far, we've been unable to find definitive proof that TikTok is or is not officially banned in China."

https://www.snopes.com/fact-check/is-tiktok-banned-in-china/