Quite to the contrary, in fact. One of the big learnings from the Google real names policy was that people are JUST as willing to be terrible under their real names.
What I think it is, if I may hypothesize, is merely that there is fundamentally no incentive to NOT be however you want on the internet. 9 times out of 10 nothing you say will be traced back to you, or will reflect on any aspect of your day to day life. I consider the internet a window into the uninhibited mindset of the average person, and that although we may find it distasteful, to censor it would be paramount to burying our heads in the sand about our own nature.
What's worrying is that rather than find avenues to deal with it in reasonable or moderated fashion, the narratives often seem to shift to the most extreme and often dogmatic-seeming angles, more as talking points than measured response.