@RagzReturnsRebooted - I kind of disagree with this, surely women (adult human females) are opressed because of our biology (sex) as we can be raped, impregnated, we bear and raise children, we are smaller (generally, not me) and tend to be physically weaker than men. Gender can certainly be a way to reinforce that, but if I chose to present with a male gender (somehow) I would still experience those things.
I consider myself gender critical in the sense that I don't agree with gender stereotypes of anything like clothes, jobs but I don't think getting rid of all of that would magically solve all the problems of sexual inequalities.
You are using a very narrow definition of gender. It's not just how we dress or present ourselves, what jobs we're encouraged to go for etc.
We are oppressed because we are female. That's the 'why', as TheInebriati said. We all seem to agree on that. I hope we also all agree that female is not an abstract concept. Everybody knows that new human beings grow in female bodies and not male bodies. Everybody also knows that men are generally larger and more physically powerful than women.
Gender is the 'how' and it operates far wider than clothing choices, beauty practices and job choices.
Rape is gender.
How we treat preganant women is gender.
How we treat mothers is gender.
FGM is gender.
Child marriage is gender.
Female infanticide is gender.
Inheritance is gender.
'Sex work' is gender.
Surrogacy is gender.
Porn is gender.
Capitalism is gender.
Trans ideology is gender.
Marriage is gender.
Bla bla bla. I could add and add to this list.
Of course you can't just opt out of all of this by 'presenting with a male gender' (
). Men know what a woman is.