Surely "gender" is nothing more than stereotypes which relate to sex?
The stereotype that women get emotional as a result of hormonal fluctuations over the course of a month is incredibly closely linked to biology.
The stereotype of women staying at home whilst men go out to work is also closely linked to biology, but less so. It is obvious that the partner whose body needs to recover from pregnancy and childbirth, and who can breast feed, is the one who it makes more sense to stay home, which makes it more likely.
There is the stereotype of women doing more cooking and cleaning than their husband. To some extent this stereotype is a natural consequence of the stereotype that women are more likely to be at home due to their child.
There is the stereotypical dirty slut, and there is the stereotypical boring conservative housewife who has no interests or value other than her caring responsibilities.
Then there are the stereotypes such as short hair no make-up is right for men, and vice versa. Nothing whatsoever to do with biology.
It seems to me that (to generalize) TWs are happy to adopt the stereotypes that are ultimately meaningless (long hair and make-up and dresses). And they are happy to adopt any stereotype that relates directly to biology - pretending to have fluctuating hormones, pretending to breast feed - as that is validating. They are happy to adopt sexualized stereotypes - to play the role of a slut (in their fantasies at least), the role of an expectant hole.
I have never really seen any evidence of TW taking the stereotypical selfless caring role, where a woman's whole life goes on hold for months or years or even decades in order to make life as good as possible for a parent, partner or child. They don't seem to fall into the stereotype of running around flustered making three different meals because DC1 and DC2 like different food and DP doesn't get home til late.
TW seem to me to be very much men who simultaneously conform to many male stereotypes, whilst also conforming to many wrong-sex gender stereotypes. The stereotypes that are abandoned tend to be the difficult male stereotypes (protector and provider), and the stereotypes not adopted are the difficult female ones (like putting others first, stepping up and taking the caring role).
TW are simultaneously very much gender conforming (to two genders), whilst having aspects of male and female gender non-conformity... and every which way you look the TW is on the "winning side" - it's all about the advantages and never about the disadvantages.