I think you should be more concerned about easily accessible things like hentai sites, weirdos, elsagate, etc. I don’t know if there are any free hentai games on Steam (and if there are, they shouldn’t be free), but children certainly shouldn’t have free access to Steam (or even the internet in general), and if some parents kids can just spend their parents money on hentai/porn/whatever, then maybe those parents should rethink their parenting methods and pay more attention to their kids, imho.