Well, firstly, that is not the argument that regulators are using against TikTok. To the contrary, the concern they express is one about national security, data scraping and spying. However, to speak to your point, I have never seen influence by China of this nature. Whereas I see massive evidence of such influence by the governments of the US and Europe.
See this article by Jacob Siegel. While he is a conservative and I am a leftist, I totally agree with him on this:
"Since 2016, the federal government has spent billions of dollars on turning the counter-disinformation complex into one of the most powerful forces in the modern world: a sprawling leviathan with tentacles reaching into both the public and private sector, which the government uses to direct a “whole of society” effort that aims to seize total control over the internet and achieve nothing less than the eradication of human error."
Thirteen ways of looking at disinformation
www.tabletmag.com