Personally, for me it’s the idea that just because you don’t experience something (dysphoria, or being a gender other than what society expects of you) that doesn’t mean those experiences aren’t valid.
I get sooo tired of the response “I just don’t understand! I love being my AGAB! Why can’t you just get over it?”
Very annoying when people just kinda assume nocritter else experiences anything differently from how they do :| “Oh yeah, everyone’s like that!” But no, actually :-\