This is such an important point - so much of what they mean when they say 'feel like a woman' or 'being a woman' is based on stereotypes. Clothing, make up, hair, nails, etc. etc.
When actually, what makes us women is our biology - nothing to do with our outfit.
Germaine Greer did a really good interview about this (I saw it on a thread recently) where she outlines the difference between female and feminine that struck a chord with me.
Femaleness is our biological reality - so for example periods, pregnancy, breastfeeding, menopause - are all uniquely female experiences. Obviously I know that not all women will experience all of these, but ONLY women experience these.
Whereas femininity is the 'role play' of women in society - and it is usually culturally shaped. What we wear, how we look and how we are expected to behave. The hair, the nails, the make up, the outfit etc.
And now we are expected to go along with the idea that femininity is what actually makes us female, rather than our biology. So the 'role play' is supposed to be the authentic thing.
This is because men want to be able to opt into it, and they can't have the biological experiences, so they claim that what makes a woman is all the dress up etc. etc. So they get to take part. Usually for fetish reasons btw.
But our biological experiences are so important, and they are usually the reasons we are discriminated against as women. Think about young girls who experience their first periods, and feeling dirty and embarrassed by a perfectly natural biological event. Now periods are being used as fetish props for men.
Or the way breastfeeding is often seen as embarrassing or a bit unpleasant in public or whatever. This is because breasts are supposed to be pert and sexy, for men to enjoy - which is ridiculous because breastfeeding is literally the actual function of breasts.