Manners is getting harder to teach because of video games the internet. It's not because the either are bad, it's just how people use it. So many young children play games like COD and GTA, and games like that, as well as the internet in general, are FILLED with jerks with jerks who let all their frustrations or problems on the internet, or maybe they're just plain sociopathic. Going back to COD and GTA - those are violent and brutal, as well as very explicit games. When given to an adult or teenager, they know that it's inappropriate and just a game, and thus don't take it the same way that young children do. It's like soaking a sponge in poison.
Everything I stated above is the reason for their defiance. And while it's good that they can advocate and speak up for themselves, they are being given absolutely awful teachers - people on the internet. Sure, not all communities are bad - case in point, Imgflip. But there's so much nastiness, it's hard to keep them from learning all the wrong things.
But that's just my two cents. Er, paragraphs.