I'm not sure I understand the distinction you're making between "slur" and "epithet", but I suspect you're reading too much into that choice of word.
The point I was making is that when you say "The protestors are framed as crazy"... it's not just framing. They sent a picture of a gun to a speaker--that IS crazy. If you can't even quote an entire sentence about the people you're defending, it's you that's doing the framing here.
And yes, the author clearly has a bias. But if you refuse to read anyone who has a bias, you'd better just give up reading. You certainly showed a bit of bias in your selection of which parts of that sentence to quote. It seems like your real complaint is that you don't agree with the author--if that's the case, then this is your opportunity to say why you think the author is wrong. That's how you have a discussion with people you disagree with: you don't accuse them of bias, you don't try to shut them up, and you definitely don't send them pictures of guns.
The truth has power. If what you're saying is actually true, you can get people to recognize it without making inane accusations, silencing naysayers, or making death threats.
To be clear: I think it's perfectly fine to call someone a TERF if the accusation is true, and it's bad to be a TERF. But sending pictures of guns to people has no place in a civilized discussion, and we shouldn't be tolerating that behavior or covering it up.