You are neglecting the cost-benefit of temporarily jumping to the wrong conclusion while waiting for more conclusive evidence though. Not doing anything because evidence that this is bad is too thin, and being wrong, can have severe long-term consequences. Restricting tiktok and later finding out that it has no detrimental effects has essentially zero negative consequences. We have a word for this principle in my native language - that if you are in doubt about whether something can have severe negative consequences, you are cautious about it until you can conclude with relative certainty that it is safe, rather than the other way around, which would be what you are suggesting: Treating something as safe until you have conclusive evidence that it is not, at which point a lot of damage may already be done.