Yeah, sure, sometimes. I've followed enough far-right links to the Unz Review and I'm not sure how else you'd classify Israel Shamir, or for that matter Ron Unz himself.
I think the issue I have with it is that rather than arguing the substance of someone's points, you're speculating on the motivation why they claim to have that belief - it's essentially saying "obviously people in the in-group could never actually hold your beliefs legitimately, it's because you want to fit it or because you are psychologically malformed". With fisher (i know less about unz) he did seem to have some sort of mental illness that consumed him, but honestly even the word "self-hating" doesn't even seem to describe it.
The example I'm thinking of is Gerald Kaufman who clearly had a huge personal disconnect with the zionism he wanted (I'm pretty sure he always claimed he was Zionist at heart) with his extreme rejection and rhetoric against Israel. It's clearly complex, but I think we're on clearer ground talking about what exactly he said rather than speculating on the nature of his thoughts.