I believe it s akin to alcohol or pornography. Most people can handle alcohol. They have a drink now and then. Other people can t handle it. They become alcoholics.
Most people look at pornography without it ruining their lives.
Others become obsessed and try to turn the images into reality. They become rapists or pedophiles. An incredibly high percentage of sex offenders in prison say they started out looking at pornography. I think the problem of violence and teens is similar. Most teens can play violent video games, watch violent movies and listen to death metal with no ill effects.