Could you explain it then? No one has ever came up with a good argument.
You can stray away from politics and religion since they have nothing to do with this, lol.
For starters, I feel that the problem is not that six is over-vilified, but excessive violence is given too much leniency.
Killing and injuring others, as far as I know, isn't a basic human need. It's used to get those needs, but it's a means, not an end. In games and movies, it is used to excite. Sure such excitement can be addictive, but but it doesn't carry the social stigma that sixual stimulation receives. six, on the other hand, tends to arouse, and it's a basic human instinct, so unlike violence, the body naturally desires it. So depictions of six tempts the body more than depiction of violence. And aside from the whole "exposing youth to things they're not ready for" thing that I honestly would rather just avoid, some believe that artificial sixual depictions, as well as artificial sixual stimulations, are morally wrong.
Again, I feel the problem is with going too easy on the violence aspects, rather than going too hard on the six aspects. Violence can arouse some people, it is more much easily imitated by youngsters even if they do understand six, and in reality, it's not nearly as frequently considered acceptable to engage in as six is, even if we go by the most rigid definitions of "acceptable" in our society.