You're saying this like it's bad but I'm not sure it is. If kids want to use voice chat they can, all they have to do is lie about their age. Default off for children is a good policy, and allowing them to get it around it with some effort probably is too. Seems like what's important here is that unsuspecting children aren't thrown into voice chat and immediately called the n word or something. If the kids are prepared to be bullied then they can go ahead with voice chat.