Japan has incredibly low crime and sex crime rates compared to other developed countries, while excesive porn consumption does lead to more extreme porn that doesn't mean it leads to sexual assaults, there are studies that show that when countries legalised pornography the sexual crime rates plumeted. Give a victimless outlet to people and they will manage their urges in most cases. The ratio of pedophiles to child molesters is insanely low (in fact two thirds of all child abuse is committed by non pedos, just for the sake of the power high), most pedos spend their entire lives either consuming child porn or fictional child porn, a lot of the ones who consume the real thing are making the change to the fictional one because they realise they are actually helping hurt the children.

From the studies I've read and my personal experience over the years on the internet I can say that a victimless outlet saves children in the end.