I'm still unconvinced that tiktok holds much data that is valuable to any government. As a node in the information tree it might have some marginal utility but my understanding of tiktok is that the data primarily is how much you enjoy cat videos. Maybe the chinese government can work out your sexual orientation, or that you are anti communist, but this is only a problem if you live in China.

Even if the data is valuable, as far as I know there are no backdoors available to tiktok that aren't available to other apps (e.g any tencent game). The security model at the os level seems to be the proper place to ensure privacy, and the witch hunt against tik tok seems to only exist because it is popular.