I see where you're coming from, but Youtube isn't nearly as opaque as Tiktok. You can actually search for videos on youtube, typically content is longer and has a higher production quality which reduces probability of doom-scrolling. As someone else mentioned, TikTok is intentionally designed to be addictive and gamified, much more so that youtube or facebook.

And, objectively speaking, the US government is far preferable to the CCP. The US has it's issues and has made mistakes in the past, the CCP is still putting Muslims in concentration camps and exercises regular authoritarian controll over it's citizens. Militarily, the US is allied with most EU powers (including France) and generally has good intentions for it's allies. China, on the other hand, finds itself on the outside of most alliances, and considering that even their own people are treated poorly, I can only imagine that their intentions for others are not positive.

American tech companies take your data and sell it to advertisers, I don't like it, but they do. The US government only accesses it if they have a reason to do so and subpoena the specific information needed. The Chinese government? I have no doubt that they're collecting data for much more nefarious purposes. Intelligence indicates that they've been improving their military forces massively in the last several decades. It wouldn't be hard for them to subtly start slipping in propaganda into the tiktok feeds of countries they intend to invade, and then they'll have local-national support.

I think it's easy to look at this and say objectively that it's worse. If Youtube or Facebook were owned by France or Germany I would hold the same belief that tiktok is worse. It's not fear of some mysterious "other", but fear of a proven enemy to freedom and human rights, China.