"Viral at any cost". Encouraging children to potentially put themselves in risky or dangerous situations just so they can get a dopamine rush isn't healthy at all. I've had an instance of a child (probably about 10-12 years old) run out in front of my car, do a "dance" then run back on the pavement while their friends recorded it on their phone. The child was wearing a TikTok hoodie, so I'm assuming it was some stupid attempt at getting themselves on to the algorithm.
My sister is a school teacher, and she's noticed changes in kids using the app, they're completely failing to maintain any kind of attention in class after a couple of minutes. Where phones have been confiscated, the kids often have extreme reactions to being separated from them. Some have literally ran away from school after being told to hand over their phone, which obviously comes with a whole other set of problems.
Educate kids in moderation, we've got the tools in iOS and Android to limit their use. Use them.