The progression of that thread was entirely predictable after the early mod intervention.
If you enforce civility of presentation without enforcing civility of content, all you do is create a safe space for minimally-disguised bastardry. A Klansman is still a Klansman even if he knows which fork to use.
We've all been to this rodeo before. Every Sarkeesian thread pops up on GG Google alerts, and they dispatch a few people to repeat the same tedious, disingenuous, slanderous sealioning bullshit. The level of thinly-disguised misogyny involved is usually more than would be tolerated in an analogous race or religion thread.
Recently, those threads have seen the early deployment of justified mass public scorn, which has on occasion disinfected the thread sufficiently to allow a productive conversation to arise. But that doesn't happen when the gators are running free; few posters worth reading are willing to bother with a thread full of that crap.