The way I see it, many of her stories are thought experiments. For instance, on Gethen, the essential question is what could a world look like that has no concept of sex and gender? Examining these "other worlds," or even mulling those questions over, can lead to re-examining how sex and gender influence our own world.
In her short story "The Mattter of Seggri," (contained in the compilation of short stories, The Birthday of the World) the question is, what could a world look in which females greatly outnumber males. On Le Guin's planet Seggri, only about 1 in 6 conceptions result in a male fetus and, due to the fragility of male babies, by adulthood there is only 1 man for every 16 women on the planet.
The consequences of this imbalance are essentially a reversal of gender-dictated public/private roles in our own world, here on Earth. On Seggri, boys are removed from their homes around puberty and taken to "castles" where they learn how to be men. In order to ensure the survival of the species, men are restricted to two endeavors in life- competing and having sex. Under their norms of masculinity, they learn to compete in various athletic competitions, often for the entertainment of women. And, they live in "fuckeries," institutions that essentially make them nothing more than sperm donor prostitutes.
Everything else pertaining to the public sphere- running the government, raising families, going to college, having a career- is considered "women's work." While women have sex with men in the "fuckeries," women are only allowed to marry other women. Men, it is said, are little more than brutes- desiring nothing more than physical pleasure and competition with other men. A real person (ie- a woman), is not capable of having a real relationship with such an animal.
Upon reading this story, I found the parallels to our own world interesting. Predicated upon "necessity," the role of men on Seggrei nonetheless seem absurd. Perhaps because they vastly outnumber men, women hold all of the real power and they use that power to essentially effectuate a giant affirmative action program for women. Rather than treating men as the human beings that they are, men are given a very restricted role based on the beliefs that (a) men are animal-like and (b) that the human race would die out if men did not fulfill this role.
In this fiction, how the women in Seggrei treat men underscores the historical injustices that men, as a class, have imparted on women here on Earth.
First, the one's who hold power, women, deny that men are full humans in the same way that women are. In Le Guin's story, she writes of a man who falls in love with one of the women who comes to visit him in the "fuckery." He wants to leave the castle and marry her. The woman rejects him, thinking:
"...[D]espite his romantic talk of love, he was a man, and to a man fucking is the most important thing, instead of being merely one element of love and life as it is to a woman. (48)"
Does this sound familiar to anyone? It should. On Seggrei, we see that the stereotype of the True Nature of Men is the same as it is here on Earth, where movies, the mainstream, and emails urging men to enhance their penises barrage us with the message that men only care about fucking. They are animals, and because of that, on Seggrei women are "justified" in keeping men out of what is thought of as the real world and excluding them from real relationships.
On Earth, of course, we deal with this Male Problem in a different way. Social conservatives insist that marriage is an institution that is necessary to keep the Naturally Promiscuous Man in check. The woman, it is said, polices male hyper-sexuality and, also, is the subordinate "complementary" half to the male, around whom marriage really revolves.
Two, in addition to the male stereotype keeping him confined to de facto sexual slavery, on Seggrei, men are kept ignorant, unschooled. In the story, the man who had fallen in love with the woman who visited him in the fuckery wrote her a letter, expressing his love for her. The woman reacted in the following way:
"She received an immediate answer from [him], a letter begging her to come and talk with him, full of avowals and unchanging love, badly spelled and almost illegible. The letter touched, embarrassed and shamed her, and she did not answer it." (48)
Here, we see how men on Seggrei are in a Catch-22. It is, supposedly, in their nature to only want to fuck and compete, and so they are denied an education. Yet, because they are denied an education, they remain ignorant. This ignorance only reinforces the "natural" stupidity and animalistic nature of men. The woman in this story ultimately rejected the man as a lover and true partner in life, in part because of his "inherent" stupidity. She was embarrassed for him and of him. Instead, she sought business and romantic partnership with an equal, another woman.
Again, the parallels to our own world are quite obvious. Throughout history, men refused to allow women entry into the public sphere- into universities and learned occupations- because of Woman's Natural Delicacy, Stupidity, and Reproductive Capabilities. While men have excluded women from the public sphere throughout history, some men nevertheless claim that men have created pretty much everything good in the world as though that is a testament to the Inherent Superiority of Men, and not a testament to something else men were really "good" at- keeping women out of the public sphere. For, had aliens visited our planet a mere 50 years ago, they would have been justified in believing that men vastly outnumbered women here on Earth, given the extent to which men afforded themselves a giant affirmative action program in the public sphere.
In addition to highlighting injustices based on sex, gender, and sexuality in our own world, Le Guin's stories demonstrate that just because customs are a certain way here on Earth, it doesn't mean they ought to be that way. Always, there is room to re-think our institutions and the "self-evidentness" of what it means to be men and women and what that, in turn, means for relationships and institutions.