Yeah, that's the one thing I don't like about Toady's moderating. People can sometimes get away with insulting others, or even their entire opposition as subhumans, literal terrorists, supporters of [insert blatantly immoral and/or criminal act here], etc. and not get banned, but the threads will be locked. In the last few months this has happened at least two or three times in large threads.
Edited for clarity.
While I can agree that it happens, the time I saw someone who acted like that with my own eyes was BurningPet, and while the thread got locked Burning was also instant-banned for flaming. That was the Abrahamic Traditions discussion thread, and while that thread never rose again I created my all-religions thread sometime thereafter and we never really had a problem. I think Toady locks them because it takes two to argue, and usually after somebody says something incredibly flammable the entire thread goes up in flames. Although I get the impression that maybe smeep acted like that as well, she has been banned too.
About GWG: I never got the idea that he was being malicious, although granted I didn't have much time to interact with him before his banning. He did always strike me as somewhat... haughty, I guess? But he never really came across as "intentionally causing problems" and more as "trying to be honest and forthright in the wrong way". In the cases of arguing about the rules, he was trying to change what he honestly believed were mistakes/imbalances in the game, but went about it in such an insistent, obnoxious way that the GM got fed up. Speaking of which, given that particular trait, mild autism spectrum may have been present, because some of the people I know who fall on the autism spectrum act that way. While I would say I haven't seen as many fights break out and Toady hasn't had to moderate quite as much with him gone, saying that "the forum is better without him" sounds dangerously close, at least to me, to "my life would be better without (x person with autism spectrum disorder)", so I'm not comfortable saying that the forum is a better place now.
It is telling that the person who started the petition to bring him back was banned a couple of months afterwards, although for something unrelated. It seems to me that there are three types of people who get banned: spambots and obvious trolls, people who you can see it coming from a long way off, and people who sass Toady via email or something after a mute.