PC, you do raise an interesting point. On one hand, maybe pilots should be smart enough to consider the source of what they read online. On the other hand, maybe union folks ought to be held to a higher standard, even in what they post from personal accounts.
My two cents is that reps are absolutely entitled to posting their opinions online, especially when everyone knows their handle. Line pilots ought to be responsible for considering the validity of such opinions. I's also say that perhaps while a rep is /in office/ and actually volunteering, public posting ought not be so volatile.
But once that person is done serving or has moved on from the company, who cares? Is posting online substantially different than talking with pilots in a crew room? (Assuming that person isn't using a clandestine handle that no one knows about while they attempt to sway pilot opinion while acting like some sort of oracle... cough cough...)
FFT, I guess.