" The Philosophy of life" eh! bobbi? Books have been written about it, but my very superficial comments only apply to CB and not to any other sections, putting my own personal slant on the topic.
CB is predominantly female, at a guess 95% female and 5%male. The nastiness, mainly comes from that 95% ( you have excluded the trolls in your question who were entirely male)
Intonation and meaning are often misinterpreted in email form despite the LOL.:-) 0-( etc and I think that this may well pose problems.
Brenda is correct, CB is a microcosm of the real outside world with the widely varying personality traits.
Many people need to be liked, they need to be told that they are liked and they need to feel needed.( I don't) Many people cannot stand the bonhomie of some posters and if replicated thread after thread, post after post, day after day, week after week....boring ( I do)
To liven up debate, they post contentious comments, not necessarily believing them, but just to "liven things up" (I do)
Many people write things and then regret them (I do)
Many people have a "chip on their shoulders" and cannot hide this, whilst others are vindictive and can't help showing it.
sqad is happily married......big turn off.
sqad sh@gging next door neighbour.............rotten old sqad, time for a thread.
CB is very similar in my opinion to the act of Les Dawson and his mate dresses up as old women....slagging someone off............good fun.
Bottom line...........you are looking at a screen which alleviates the boredom of your life all, or at a certain time of the day.