What silme. Anonymous published their smear campaign in full already, including their little charts of who they think Anonymous is. Backing out of conferences will save them the embarrassment of having to answer questions and gives them a chance to smear Anonymous. Given that their primary smear technique was harassment, planting things to discredit and other agent provocateur slime, HGBary's claims of death threats carry no credibility.
We should look to the perspective of the victims to gauge things instead. Try this one on for size:
the revelation of terror tools used so brazenly against political opponents in the private corporate sector is disturbing, to say the least. While the notion of paid political operatives subversively using social media to discredit opponents has long been suspected by many, here we have evidence that these tactics are, in truth, fairly common among those who can afford to deploy them. That commenter who always shows up to hijack a comment thread on a specific topic may very well be working for $250/hour
What a bunch of unAmerican trashbags.