that seems very material, for the US population and Bytedance's verbal commitment to the govt. At this point, it's obvious that data of US citizens (a large chunk underage) has been heavily shared with what is perceived as a rival state
If you want data on this assertion research "capitalism with socialist characteristics." If you want the data straight from China read their 14th 5-year plan (I wish the US had these kinds of plans) translated by Georgetown University here [1]. China is very open about what they are doing in published writing.
If you want more information read "The World According to China" by Liz Economy. I can suggest about 10 other books too, but that book was published in 2022 and is the most relevant book I read. Unfortunately China's government from a Western lens is such a complex topic I can't simply link to one article about how China runs its economy and "private" organizations to prove my point. This complexity unfortunately leads to people making false assumptions about how China operates without the requisite knowledge - and then deciding how we should make policy decisions towards China.
[1] https://cset.georgetown.edu/publication/china-14th-five-year...