My first point was about male sexuality but the larger point is that you don't, in my view, create gender equality by muddying the very simple idea of gender until it has no meaning to Leftists.
I've agreed with the general points you've made on this topic but here I think you're going overboard when you say gender is being muddied to the point of meaninglessness. The notion of gender as something apart from the sexes has a meaningful referent, the entire body of ways people express themselves in the terms of human sexuality (butch, femme, etc.), and this distinction has fairly old roots in anthropology so employing the term "gender" in this sense isn't unconventional or obscurant. I think the tendency of leftist literature on gender to deny biological reality undermines how relevantly it describes gender relations between actual human beings, but I don't think this makes the study of gender itself meaningless.