On top of knowing who you are, where you are, whether you’re single or married, whether or not you have children, where you work, when you work, what your interests are, what your embarrassing interests are, etc. etc. etc.
People are weirdly blase about this but, if you use TikTok regularly, they have such a wealth of information about you that an intelligence agency would find it trivial to compromise you. You’re just gambling that you’re not worth compromising.