The whole argument is that China can influence TikTok to change content to hide truths and harm other nations, which is soon going to apply to the US too, if not already.
imagine if the US removed anything against the Apartheid state(Facebook already does this, any news showing what's actually happening in occupied Palestine is removed), or if it does another invasion and it removes any reports going against the Governments story?
The difference is the U.S. has never been challenged in tech and influence, and now they have and they don't like it, they don't like to live under the mercy of another country with its own interest that doesn't match with the US.
Truly, the US is finally getting a taste of its own medicine.
With all of that said, I can't deny that the US would still be probably better than China in freedom of speech.