I think the mods do a good job here, and are obviously trying to keep the really obnoxious posters off the boards, but when you're talking about a site that is used by 20-odd thousand people, you're going to get some disagreements. Throw in the fact that this is an international forum and that just adds further scope for conflict, as cultures clash and command of English varies. As is always the case, you can't keep everyone happy all of the time.
I do agree that there are some issues though. It is embarrassing seeing the same wrongheaded and defensive points raised again and again, especially in the kind of threads Persephone is referring too. I can get why that grinds people down and causes people to reconsider posting here. Its tricky to deal with though as its not always the same people, and intention can be hard to read, which makes going straight to banning seem harsh, so I have sympathy with the moderation team for the difficulty of their job. They are an order of magnitude better than the GAF mods, who could be petty and spiteful. A little bit of internet power definitely went to some of their heads over time. There is always room for improvement of course, but I think we should be somewhat grateful that the admins have done a far better job of keeping the arseholes away than the vast majority of other videogame boards.