How much do you know about Radical Feminism? Not too many of us here would adhere strictly to radical feminism either. We will have certain common views with RF but won't be completely bound by it's ideology either. TERF was dreamed up as a slur based on the fact that some of the first people to raise alarms about trans ideology were radical feminists. But it was very, very quickly applied to anyone disagreed in any way with the ideology, not just radical feminists, not even just feminists or in fact, not even people who want to 'exclude' trans people.
It was a way to scare people into shutting up but as it's not a slur with a long history of being used to abuse. It was very easy for people who believe in reality, to shrug and say, 'sure that's what I am,' when called TERF. It's why Dave Chappelle can declare himself Team Terf, or why GC people or anyone else who understands reality can call ourselves Terf. It's the easiest to reclaim slur in history because the first that most people heard of it, was when they realised that they are one and the people calling them it are batshit.