Maybe I'm lucky, but I find it really easy to just disasociate with online comments. Whenever I read something hurtful or mean directed to me on the internet, I can very easily just shrug it off as "some internet person" and move on, although admittedly I've never been target harassed like some people have, which I'm sure is distressing. I think part of this was growing up I was always told: "Don't use your real name online! Don't give out your personal info!", and so for me, being online was always about being someone else, a different persona if you will. These days that seems completely out of the window, everyone uses their real names everywhere, uploads actual pictures of themselves and generally their real life seems directly integrated into their online life, which is just unthinkable for me. This probably makes online abuse just that much more personal for them?
I suppose another big change of course is that all the small forums that used to make up the internet are now exceedingly being consolidated into just one or two sites. Again, back when I was a child trawling the internet, if you didn't like one forum, you just hopped to another, and there were always plenty more (sidenot: remember the 'affiliate' tags on sites? I miss those. Made the internet feel more like a big group of communities, but I digress). Of course now, if someone is being harassed on twitter or facebook or something, well, they're not going to go somewhere else because a lot of the competition no longer exists anymore.
I don't really know where I'm going with this comment honestly, I'm just ranbling. What I do know is that regulating the internet is, and always has been, completely futile. So long as someone, somewhere, can spin up a forum on a VPS or on a computer at home, and people can connect to it, there's going to be sites hosting every kind of content imaginable. If they can't even bring down the Pirate Bay with the music industries power and money, they'll never stop people saying nasty things.