Ok I think this is a misunderstanding about what it means to "have tiktok". If you mean in the context of your house sure.
But I had this same conversation with my parents. There is no reasonable way to actually prevent a kid from having access to tiktok in some contexts. Parents who say their kids don't use tiktok because it's not allowed at home are just incorrect.
My dad doesn't get that when she hangs out with friends or goes to school, she IS seeing tiktok content.
I wonder if he realizes that's because no one around him respects or likes him?