Accusations of sleeping with journalists that promoted her game was the catalyst, the Quinnspiracy, there's been a beef with game journalists for years for their questionable reviews, corporate shilling and condescending demeanor towards their readers.
From the Quinnspiracy came GamerGate at this point it switched focus directly to squaring off against game journalists and sites, at which time those same journalists being accused of unprofessionalism, nepotism and other such things, admittedly without many examples of proof, but something that was suspected came out with similar articles in a very short period about the horrid nature of gamers, later it was found out that their was a mailing list where many of these journalists from different sites talk to each other about what they're writing, collusion.
That's when they when went "gamers are" misogynists, racists, homophobes etc, specifically anyone that is part or supports gamergate.
Then not your shield came out to prove that women, minorites and lgbt were part of gamergate also and not a hate movement.
Then accusations of sock puppets came out to dismiss all that, Tim Schaffer did a very cringy joke about this, I still cringe when I think about it.
Then journalists went and brought in Anita as part of the conversation of how she is one of the main targets of GG along with Quinn and Wu, GG=harrassment.
I kept up on those early GG threads on /v/ because I found the whole thing so damn amusing and I can honestly tell you, Anita was pretty much never brought up in those threads.
Then Moot banned all GG threads off of 4chan supposedly because he feared another legal scandal similar to the celeb nude pic dumps, which was unprecedented, sites all over the net were all doing the same thing purging people and discussion's of it, of course that only gave GG more steam.
I really can't say for certain what happened after that, but I know that I wouldn't trust game sites for the real story.
TLDR version? LOL!