I also know there's more to be being a woman as my biology, so maybe that's why I can accept but others can't?
There is female biology
Then there are the direct results of that biology, good and bad, like bearing children, dealing with periods, being multi-orgasmic, being physically weaker than men, living longer than men, being less driven to risk-taking in our youth.
Then there are indirect social results of that biology like the need for maternity leave.
Then there are social expectations of women’s capabilities and acceptable behaviours that are not in any way biologically driven but still affect how we are perceived and treated and which most women (the female type) have internalised to some extent.
Then there is a whole pile of cultural stereotypes around personality traits, life priorities and interests that have been erroneously mapped onto “female”
The first set of stuff just is.
The second set of stuff requires woman (the female kind) specific products, services and support.
The third set of stuff needs legal and social frameworks to ensure women don’t end up disadvantaged.
The fourth set of stuff also needs legal and social frameworks, firstly to ensure women don’t end up disadvantaged, but also to continuously challenge, disrupt and disprove the assumptions with the long term target of getting rid of them altogether.
The fifth set of stuff needs to be framed away from “women’s stuff” and just opened up to anyone.
So, of the 5 types of stuff that currently pertain to women, the only one not predicated on female biology and therefore potentially open to men is the last. But that’s just moving between culturally assigned boxes, and boxes that are different shapes and sizes depending on the culture they are in. We as a society will be much better served by working to untangle the gendered expectations altogether than we are by just moving people from one box to another and (metaphorically) cutting off the bits that don’t fit to make it work.
In other words, once you take cultural conventions out of a practical definition of woman there simply isn’t a space within that definition for males. It really is just about the biology and the direct impacts of having it.