This sentence no verb. But you still supplied one, right? Whenever you look at a person, regardless of their public gender presentation, you want to know what their genitals are, which for most people defines what a person 'really' is; they are their genitals, their sex. This is a person's primary identity in our culture, female or male. All else is tacked onto that basic definition.
Some people in the 'gender community' express a desire for a society in which gender is decoupled from sex, from genitals; for a society in which a person could dress and behave as they wish in public without making an implicit statement about their genitals.
Could we have a society in which gender is not tied to sex? In which there would be no public markers such as dress, makeup, jewelry and so on? In which one could not tell by looking at a person what sex they were?
The answer right now clearly is, "No." In a society in which homophobia and sexual political correctness are rampant, few people would risk not being able to determine a person's sex before feeling attracted to that person.
There is massive trans and homo-phobia all around (and within) us. People who loudly label themselves as heterosexual male crossdressers do their best to mimic female secondary sexual characteristics, hide their own 'male' secondary and primary characteristics, and not infrequently flirt with men while in their female personae.
A person born with a vagina is generally accepted in women's space if they can shower naked in Michigan. So long as any internal turmoil about masculine identity in kept in the closet. But publicly proclaim an FtM identity and, zoop, all that history is history.
On the other side of the coin, a known MtF transsexual is often never welcome in women's space, even when zie totally 'passes,' with or without clothes, and has lived perhaps decades in society as a woman.
The fate of those people who identify as both queer and transgender is even less fun. Transsexual lesbians and transfags. We do exist, oh, yes. And some of us are true gender guerrillas.
This diversity doesn't add up to "female plus male equals all there is." A significant number of people do not fit and/or are not allowed in any gendered space. People going in the FtM direction are not booted out of women's space into men's space. People going in the MtF direction do not leave men's space for acceptance in women's space.
There is in fact an 'other' space, for gender souls lost in the limbo of 'nega-nega-nega-negativity' (Seed in the Sahara, by Disappear Fear). Whether or not you believe in a third gender or sex, there are quite a few people being treated as if that is what they are.
There is a big part of gender that is about not sex, but power and social class. A good case can be made that what we now call gender was invented specifically to keep women as a subject class when the industrial revolution erased many of the labor-based role differences that had previously kept women in their places. A true gender revolution must also free people from arbitrary social advantage and disadvantage.
There is a strong natural tendency for human beings to form cliques. Birds of a feather can flock together only if we can tell who we are. No way are we ever all going to want to be indistinguishable, though I really don't need to know while I am walking down the street whether each person I meet has a cunt or a cock or something else. Isn't a little mystery spice for life? (Butches are so cute, aren't they?)
Gender revolution? Not to hold one's breath. We are just beginning to take footsteps along this road, barely scratching the surface of what sex and gender mean in the context of intelligent self-aware beings. No one knows what sex and gender will mean at the end of the next one thousand years of human existence.
Coming out as queer is hard to do. Coming out also as transgender is a lot like jumping out of the lifeboat.