I'm gonna say something that everyone uses to dismiss extremist views... and say I'm not going to try to do that.
I think that behavior was terrible, but also not really generally the views of folks who might be associated with "anti-GG".
Having said that...
One of the catches is that there wasn't an organized "anti-GG" side in the same sense there was a "GG" core group. To some extent the "GG" folks were the ones who defined who the "anti-GG" people were, and they strongly believed that there was an "anti-GG" group that behaved in the exact same way they did, but I don't think that really added up. Sometimes they defined an "anti-gg" person as just someone who gave a poor review to a game they liked, a woman who had a visible role working for a gaming company, or just liked having a female protagonist, or something pretty disconnected.
Most people that GG folks associated with "aniti-GG", really was more of an amalgam of various people and personalities who had various views .... but weren't centralized on a "anti-GG" identity, they were usually people associated with other things that had nothing to do with "video game journalism ethics". There effectively wasn't really an equivalent ying to the yang as far as groups and opposing views went. Certainly people "against" GG, but usually they were tied to other things too.
What was "anti-GG" didn't even have anything to do with "video game journalism ethics" and to some extent GG found these folks views or what have you unacceptable and sort formed that concept. "Anti-GG" was often a case of who "GG" thought they were and at times simply sought them out. Like I said no doubt some folks associated themselves with "anti-GG" but it wasn't quite a ying and yang. Many of the people initially identified as "anti-GG" by "GG" folks often talked about being against online harassment, and really had no clue what GG was until things grew quickly.
I feel like this process of taking an issue, expanding into an identity and tacking on ideas, then seeking out those views and people deemed unacceptable, and in some way trying to pick a sort of social media fight, is a very common thing with identity politics type behavior, and GG certainly fit that pattern. What was or wasn't "anti-GG" largely was defined by that process.