Because of the necessity to invoke biology as a primary argument vs trans, there's been an eclipse of the socially constructed principle that was so central to radical feminism. This is where sex expectations were roundly criticized, esp the feminization and sexualization of women (or gender). To counter this socialization of females by males was, in effect, a form of undermining the false distinctions and differences between men and women, upon which much of women's oppression is based. This goes much further than the concept of non-binary and is far more radical and effective. There can be no non-binary if women are liberated from their marked off, enemy status.