I feel like it's kind of useless when Steam asks how old you are or when it reminds you that a game has a mature content lol. If a kid wants it and is curious about it, he'll just click on it and proceed haha. Almost pretty much every game store out there.
I think this actually works in the opposite way. If a kid was asked to confirm their age, they will just be more curious to see the content.
This has the same energy as the "are you human?" captcha.
The curiosity of the kid will drive him to explore more and discover the real content of the game.
