No reasonable adult (in any country) would go on the record to propose that a hostile foreign government should run any part of their internal communication infrastructure. It's well documented that all companies in China are beholden to the political whims of the Chinese Communist Party; when national security is at issue, Chinese companies and the Chinese government are one entity, sadly.
I'm squinting skeptically at all the comments here that are confused about this, especially the ones with extra helpings of carefully chosen rhetoric (whatabout-ism, free speech, free markets, etc). There are no "free speech" issues here, ByteDance is a foreign company, not a US person. This is a national security issue.
If you think it's cool to allow TikTok in Western countries, please explain why it would have been fine to allow the Nazis to run the Royal Mail, the US Postal Service, and one third of the broadcasting services in the 1930s. Would that have been a "free speech" or "free market" issue?
The Chinese government has a long way to go to earn the trust of other countries.
See this list of common Chinese propaganda themes to check if they may have already influenced you. https://en.wikipedia.org/wiki/Propaganda_in_China#Common_CCP...