Japan has a very different culture though, they are more likely to blame themselves than others and will go out of their way not to dishonor other people by their actions, the west is a very narcissistic driven society where the I is important and always the victim so I think that also plays a role.
Violence in Games is normally less realistic than it is in Movies, so blame movies if anything, I think its utterly ridicules that the Government wants to play parent and spank the public , the public needs to get their shit together and be proper parents , sure give us guidelines so we know what we are potentially buying little jimmy but the moral values we chose to have or bestow upon our spawn is not job of anyone else but the parent.
If you want to blame anyone for what happens in society Blame parents first and then blame everyone else who turns a blind eye because its someone else’s problem