I think the type of sexual abuse you mention has been happening pretty much since man existed. It's just it's brought more up now then it was in the past. I mean 50-60 years ago a man could probably sexually abuse his daughter and it would just be swept under the carpet. She possibly be seen as a liar or crazy.

Rape, sexual assaults, abuse of children, murder, have always happened and will continue to happen. Porn could possibly influence some people, but I don't think you can simply throw this at porn.

There's a huge difference between some blond bimbo with fake breasts and a 10 year old girl for example.

I don't agree porn is healthy. There's been studies suggesting porn has negative effects on the brain in regards to dopamine. Porn can actually make real sex seem less interesting. There's suggestions that porn may stop those acting out sexual violence because they have an outlet with porn. However, the negative to that is that it can ruin the sex lives of couples.