Vanderhoven7: They’re not even supposed to be on here as their leaders forbid it.
I think this is an important part of it. They are so upset at the thought that others are criticizing the organization, that they will violate the command to avoid any interaction with apostates and "enemies." This means that they probably took steps to be as anonymous as possible, and anonymity gives people more freedom to push limits when interacting with others. They feel free to be as nasty as they want, since they are not going to answer for it in their real lives and after all, they are attacking people who are as bad as the Devil and condemned by God to eternal death.
The notion that they are risking their own eternal life hopes for the thrill of arguing on the internet is lost on them, for reasons I cannot fathom. The GB makes it quite clear that they are taking their lives in their hands by reading a forum like this, much less interacting with apostates.