It’s not China actively manipulating things. It’s the algorithm that was getting gamed by the right wing. It’s not like the Cambridge Analytica scandal where Facebook was working directly with companies that were trying to get Trump elected. It’s more like the pipeline on YouTube, where it’s just algorithms funneling people into what’s popular ends up being gamed by conservative people. In the US, Tik Tok was known for helping the “woke left”, so obviously it’s not the same big conspiracy controlling both.
The thing is, it can also be used for good in that it can show people things like what’s happening in Palestine without being censored by the US, like other US controlled social media has been.