This is a gross overgeneralization, which does no justice to the subject of online anonymity.
If you are going to take the generalization this far, at least inlude the group in the middle: Those who don't want to abuse anyone but aren't at risk of getting "abused" and just want the privacy and advantages of being able to debate or express their opinions without their friends, family, employers or random nutjobs interfering.
That's not a middle ground. It's part of his second group. If your boss fires you for what you said on Facebook or Google+, that's abuse. If other kids bully you at school over what you said online, that's also abuse. The US government not allowing you to pass US borders as a foreigner, because you criticized NSA, is also abuse.
You don't need to be assassinated, to have your life being made very unpleasant by others, when you say things online that they don't agree with.
Allow me to present some "middle-ground" scenarios, from the top of my head:
- Your spouse gives you trouble for something you said on a relationship advice forum
- One of your friends causes drama after you express a political opinion not popular in your group
- It gets awkward at your family dinner because a couple of people found out that you posted under your full name at a BDSM forum
- You discussed some personal matter online with other people, and now the other people involved in the personal matter give you grief because you violated their trust by seeking advice or venting with others
None of these scenarios could in any concievable circumstance be called abuse. These are all scenarios which would pre-internet happen behind closed doors, in a social context where the people who would be offended by the statements couldn't hear them. On the internet, they are accessible to everyone. Having anonymous forums is clearly a better solution than creating seggregated online communities which emulate the "closed-doors" scenario which would occur in the physical world. That's not to say that the "closed-doors" scenario is outdated. But online anonymity in a forum of strangers provides an arena of expression which gives better opportunities for communication, than a strict opt-in community with close acquaintances [edit: and full names].
On the contrary, I am arguing that these are scenarios where anonymity is a good thing, but which are nowhere near the edge cases of online contributors abusing anonymity or hiding from persecution.
If you are going to take the generalization this far, at least inlude the group in the middle: Those who don't want to abuse anyone but aren't at risk of getting "abused" and just want the privacy and advantages of being able to debate or express their opinions without their friends, family, employers or random nutjobs interfering.