I saw the whole episode this snippet came from, and I feel it should be mentioned that the whole thing was very much an assault on online anonymity. The angle was that people can be very immature and very nasty via the Web when their identity is obscured, which is hardly something to dispute. However, the programme seemed to be hinting that public forums should be more regulated to prevent this being possible, which…
What annoys me is there's a very simple middle solution: You are anonymous to other users, but not the company running the site. If you do something like this, then the company has the right to out you, similar to a DMCA takedown.
With that you could have those people who want to stay hidden from others, but you'd prevent idiots like this because it'd be easy for someone to report them and have them outed. It would only take a couple of bad trolls getting their "troll bit flipped" for the behavior to be reduced.