The same can be said of every single website hosted in China, but they aren't (yet) banning all Chinese websites or all content hosted in any other countries. Why not?
The vast majority of the content US citizens view on TikTok was created by other US citizens and that content is no different than the content available on youtube or any other social media platform. Certainly China can influence what types of content people see (and they've done a lot of messed up stuff in the past like filtering out "ugly, poor, and disabled" people's videos) but it isn't as if they can flip a switch and start only showing children dancing to "The East Is Red" and expect to keep their popularity. There seems to be no evidence that TikTok is any more manipulative or dangerous than any other social media platform. Youtube is just as happy to push extremist content to increase engagement but nobody is talking about banning them.
I imagine the US audience for tiktok is larger than all chinese websites combined.
If it turns out that maybe "good speech" simply can't counter "bad speech" when the latter is applied with the resources of nation states behind it, that doesn't feel like an argument the government can win (because of 1A).
Ironically, the data collection angle is still critically important for US businesses and limiting the access and use of citizen data would be great for everyone, but it seems very clear that is not on the table for the same reasons.
American social media is motivated by money. Chinese social media is motivated by state power.