Given that there are many young soldiers, policemen, politicians or employees in security-critical environments it's not far fetched that a social media app such as tiktok which has cam/mic access is able to serve as a remote controlled bug for its owners. For what it's worth, ordinary tracking of location data is already an interesting data pile - a bunch of phones that for half a year only appear on a US military base and then suddenly appear somewhere remote in Afghanistan? Most likely they're deployed soldiers. Then look at what they post and suddenly you have names, ranks, specializations... and as said, all of that is possible with ordinary tracking, the dangers of an actual bug are magnitudes larger.
most definitely