Are the ideas being attacked or the individual in this case?
Many people simply don't know how to respond to something they dislike or feel threatened by and anonymity means they don't even have to consider a valid argument in their aggression. Sometimes race or gender or other feeling of competition are enough to make people feel threatened - not much relating to social contract or "points of view worthy of consideration and respect" then.
>anonymity means they don't even have to consider a valid argument in their aggression
Is that just speculation, or did you have an example in mind when you said that? Not being a user of 4chan's /d/ board (believe it or not!), I am not familiar with the particular controversy referenced in GP's post. Not knowing what they were reacting to, and what the reactions were, I can't comment on whether there was any "aggression" without "valid arguments" (real or perceived), but I can not think of anything that could have been posted that would be genuinely worthy of concern (that was specifically enabled by anonymity).
>Sometimes race or gender or other feeling of competition are enough to make people feel threatened
Not sure if you're referring to the commenters or GP poster, but in either case, it's hard to see how any of those could be considered relevant to the question of anonymous commenting.
My guiding assumption here is that a free, open, unfettered exchange of ideas is a higher value than preventing feelings of offense or hurt egos.
Well if you don't know what you're talking about, not being "familiar with the particular controversy", maybe you should refrain from defending the participants. Sometimes people's views really don't deserve any respect. None. Use your imagination. Granted, they're often perfectly capable of saying such things under their own name.
Many people simply don't know how to respond to something they dislike or feel threatened by and anonymity means they don't even have to consider a valid argument in their aggression. Sometimes race or gender or other feeling of competition are enough to make people feel threatened - not much relating to social contract or "points of view worthy of consideration and respect" then.