Gender, as understood now, is a mix of genetic/epigenetic behavior tendencies plus a whole shit ton of social (constructed) roles and behavior attributed to sexes.
Sex is, of course, what is dictated by your chromosomes. XX, XY. There exists some special cases that are neither.
Society can often expect of you to exaggerate your gender. For males it's usually something having to do with power and virility.
In general, breaking expectations can lead to society shaming you. This is true with whatever, not the dominant religion, drugs, cheating on partner, not marrying after a certain age, etc. It is also true with gender roles.
Most people don't express their gender completely, but take some components of the opposite gender. Mostly staying within what is acceptable with society at the time.
Some men are born very feminine (probably (epi)genetic), but otherwise are cis and straight. Same with tomgirls. These people are usually in the border of what is acceptable by society (ie. get bullied, teased, forced to act a certain way by parents, etc).
Some men adopt feminine gender expressions, through group dynamics, fitting in, stereotypes of society, perception of attractiveness, rebelliousness, etc. This, in my subjective experience, happens with people who are gay, where they might adopt feminine gender expressions to fit in with the group. I've also seen this with straight men that hang out with females that are very clique-y, for example.
It is very important to note that gender expectations change very dramatically over the years and are very different among cultures.
As far as we can tell, there is something in the brain that can compel you to act the gender that is opposite of your sex. This could be that you truly do not feel the gender you were assigned, or you would feel happier passing as the opposite gender, or plenty of other shit, but we have no idea how this shit works. Experience shows that this is not binary either. As with sexual orientation were it isn't just gay/straight, it seems to be the similar with transsexualism. It is more a spectrum than an on/off switch, and probably not one dimensional. For example, a trans-tomboy, where the gender identity is female, yet borrows gender expression from the male gender. It is also important to note that "science facts" discovered by scientists honestly trying to be objective, have proven all kinds of shit that is now considered shit science. Especially today when big money has such a tight hold on academia, one should be wary of taking science as objective and timeless truth.
To answer your question OP, gender is not only a social construct, it is more complicated than that. But either way, it shouldn't matter because the lived experience of most people is much more complex and multi-dimensional. Basically always going against societal expectations, to varying degrees. How much one can transgress societal expectations has been increasing in the west. Everyone benefits from this, since people repress less their desires to take on gender roles that in their society, at some time, were restricted to the opposite gender. Transsexualism is the ultimate gender defying societal transgression. Once all forms of transsexualism are fully accepted by society, people will be free to express themselves however they feel is appropriate to them and the concept of gender will be mostly meaningless.
Reminder all forms of oppression need to be exorcised from all societies, including homophobia, transphobia, racism, etc.
Reminder that although these forms of oppression still exist very strongly in even the most progressive societies, poverty, wage slavery, actual slavery, police brutality, gang/cartel violence are even worse and is a more horrific form of oppression and an affront to humanity than calling someone jokingly a fag.
Mostly agree with pic related.
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