Kids are not stupid, though. They know about the arbitrary age limit, and they know that if they are under that limit, their service is nerfed and/or not allowed. So, the end effect of COPPA is that everyone under 13 simply knows to use a fake birthdate online that shows them to be over the limit.
Sure, it's one of the many rules that's bent and broken on a daily basis. Doesn't make it any less stupid. And it falls on the community owner to enforce, which is doubly stupid, as the only way to prove age is to provide ID, which requires a lot of administration, and that data then becomes a liability.
I was one of those kids at one point. In meatspace we have ways to deal with it and online we do as well. Of course if there is no risk to a business then they will put no resources into managing that risk.
ah to be 13 and having to lie about being 30 to not be banned from some game. so later you can be 30 and lie about being 13 to be able to play without too much ads.