I think you make many good points. Slight tangent: Why isn't EU more concerned about TikTok? While it is very difficult to prove, various studies have demonstrated that TikTok pushes more content favoring the Chinese Government (CCP).
In my anecdotal experience of one, American platforms are way faster in pushing far-right content on me even though it has to be clear to the algorithm that I don't want such content.
The timeline doesn't align for that at all. National security concerns were raised before the Pentagon banned in in 2019, then Trump ordered it to divest in 2020.
No doubt that it became an argument by some more recently, but it was just another straw on the already broken camel's back.
it's not difficult to prove. In the wake of the tarrifs, everyone in the US got Chinese manufacturing videos pushed to their feed so customers can buy direct from factories and avoid huge markups by a middleman.
I don't think Occam's razor applies here. Before the tarrifs, Donghua Jinlong glycine going viral was a silly Internet thing, but the tarrifs are big business and it might come off as a tin foil hat theory that the CCP exerted control over TikTok to push videos that undercut American companies in the face of American tarrifs, but geopolitics is very big business. Believing that those videos came up organically seems naive because this shit is a big deal with far reaching global ramifications.