What? Why are you doubting that?

I can't even search for porn on cellular networks and I'm in the US.

Hotels, Starbucks, my job, the library - they all block porn. The idea that kids just have free access to a wild internet is legitimately made up. Schools block that stuff too - universities, even.

As I've said, this solution is not solving this problem because this problem legitimately does not exist. It's solving a different problem. What that problem is, is for you to find out.

My cellular network (Google Fi / T-Mobile), as far as I can tell, has zero content blocking. Hotels used to officially put porn on the TVs via pay per view. I'm very skeptical that they widely block it.

I have high-school aged kids; they all trade techniques for getting precisely that "free access to a wild internet". It's a game of whack a mole, and school IT administrators are on the losing side.