So here's the thing, gender roles and all things that a gender represented is completely made up by the people who participate in that society. And even then, there's going to be vagueness, especially when population size grows and grows. What it means to be man, or woman, or Lhamana or whatever will change as the population changes. It's fluid. Equating sex to gender is easy to refute. If male = man, here's a nice picture of this man, thusly so because he is male.
View attachment 11868
Look at that man. He's male, so he's a man.
Counterargument might be, an ADULT male. Well, you just made an admission that gender is not definable by sex alone, thus sex =! gender. Whatever the society determines is what goes. I always got the impression in classes that gender is an idealistic expectation, though what defines that idealistic expection is incredible wide across cultures and incredibly fluid since the population changes all the time. And yes, gender is related to sex, but since culture and society is complicated, so is gender. Sex is simple, well, in comparison.
The extent I can go into gender is limited due to having just a bachelor's degree and not a Ph.D, and being graduated nearly 20 years now, so it takes a long time to formulate responses. It's easy to learn, hard to teach. Plus my Anthropological interests have never been into anything gender related. There is one particular line of questioning relating to transgenderism that I've had that is better suited for some in the field rather than an internet message board, but that's about it when it comes to gender.