If we wish to have a more academic discussion of gender, there is one aspect that has always somewhat eluded me. That is: there are too many (mathematical) degrees of freedom between allowing genders to be whatever they wish to be, and having genders at all. The solution is of course to let people what they want to be and not worry about it, but I prefer mathematical completeness when possible.
The Obvious
Hopefully we can all agree that imposition of behaviour models based upon elements of an individual that they have little to no control over, is wrong. This can apply to all manner of demographic elements, such as race, gender, ethnicity, etc.; but of course we'll focus on gender. Because something happened in the past over which I had no control, should that change my available options towards how I can choose to live my life in the present? I'm going to sidestep the word "should" for now and avoid having to conceive of and build from scratch the concept of morality; we'll work from intuition. Options that are available to me should not be eliminated through social arrangements simply because of this aspect of my being, over which I had no control.
For example: just because long ago a person might have been born with a female body, that shouldn't prevent them from joining and succeeding in the military. This is in many ways orthogonal to the notion of gender, but of course culturally it plays a huge role into it. You can call this person whatever you want, you can call them a woman (in your own head) even if they call themselves a man. At the end of the day, the genitals they started out with shouldn't define their life options with respect to options that would be available to them if it weren't for our social norms and social arrangements.
If you believe they're a woman because they were born with that female body (with no choice or consent on their part, I might add), fine. They can still use the name "Rick", because that doesn't have anything to do with their genitals. They can still use the pronouns "he/him" because when we're referring to someone, we hopefully aren't talking to or referring to their genitals, we're referring to the person. They can still do literally anything a man could or would (within physical limitations of course, but even then... that's a tangent). You can call this person a woman (hopefully just in your own mind), but that has nothing to do with stopping them from doing all the things men do.
This is already long enough and was supposed to cover the "obvious". I was going to also incorporate an assessment of society, whereby the above holds true assuming we're in a society that values freedom and self-expression. If we're in a more autocratic and repressed society, then the imposition of various and arbitrary roles and norms (such as gender) instead becomes useful to control the population.
Degrees of Freedom
So here's the trouble I run into.
A person who was born into a female body can do whatever they want. That is fundamental. If they want to go around doing all manner of "manly" things, including representing themselves as a man and using a man name and man pronouns, go for it. The limitation on freedoms is where it unreasonably infringes on others'. Otherwise, go nuts, it's a free country.
Next: a man can do whatever he wants. A man need not abide by particular stereotypes. A man can do the opposite of all of those if he wants; he's not tied to any one particular definition of man, or expected behaviour of man. Even in a free country, where a person can do anything, using the self-schema approach, a person can define man to be anything they feel is right, and thus a man can do anything.
At issue is that this creates too many degrees of freedom. If we permit the gender "man" to do anything, then the gender "man" loses distinctiveness. The range of behaviour for a "man" becomes identical to the range of behaviour for a "woman" or for other genders. We could perhaps say "men on average try to do this more", but we're not going to enforce that and we're still going to allow it to morph and evolve over time if it just so happens. Nor are we going to make an assessment of a person's gender by ensuring they fit into some or majority of "on average this gender does this a lot" with the allowance that they don't have to fit all of those. No, they don't have to fit any of them.
The Solution
The solution is to stop crying and just not worry about it lol. Some people will assert a gender they feel most appropriately suits them, and I do believe this will be influenced in large part by society's average conceptions of gender.
But in this sense, I've found it useful for myself personally (which I wouldn't impose upon others except as my own personal opinion as part of a cultural dialogue), to nevertheless face gender with a certain set of archetypes I personally believe in. In that, yes, men are more like X and less like Y. Even though that doesn't need to stop them from doing Y, and they can shun X if they want; for me personally that's what it looks like. I take it even further and try to understand such gender archetypes as emergent from biological and psychological evolution, since those aspects are slightly less arbitrary than random sociological schemas we might have orchestrated. But that's yet a whole other tangent as well.
Hopefully I've adequately highlighted what I mean regards how this conception of degrees of freedom, appropriately applied within a culture of tolerance, creates this somewhat nebulous possibility space for all genders.
