I think it ultimately boils down the their connection to the CCP, and social media’s general capacity to sway opinions which can be influenced by malicious design, along with the data collection concerns.
It’s a pretty interesting legal question. I don’t want a world where the government can shut down every social media site, but if we got to a point where foreign companies like TikTok just started blatant progranda campaigns I don’t think they’d last long here.