Here's the biggest problem with this book: Card's a terrible world-builder.
(Okay, the biggest problem might've been that whoever edited this book didn't feel comfortable telling Orson Scott Card that big chunks needed to be rewritten or scrapped, but I can't be too hard on our hypothetical editor: this book came out in 92, right when Card was big.)
Sure, he's fine when telling us about his world - this is a book about a matriarchy, a city ruled by women, a city where women hold power, and no man can spend even one night inside the city's walls if he doesn't spend that night in a woman's house.
Okay. Fair enough; a little ridiculous, but okay, I'll play Fantasy Matriarchy with you, Card. How do we play?
Oh, well, it's a matriarchy, but every guard mentioned in the narrative is a man.
Oh! Unmarried men cannot spend the night in the city unless they spend it in a woman's house...unless they're the men selling goods and services in the market, because those markets are open 24-7. Is there a curfew? Is there any way to enforce this particular rule, or are we on the honor system?
Spoiler: throughout the book, hahaha nope, we are on the honor system.
Oh! Uh, if we're talking construction, all of the construction workers are burly men, by the way.
Oh! If we're talking politics: the protagonist's mom has some sway, politically speaking, but every other named character with any influence in the politics of the city is a man. So in this matriarchy, Card gives us one (1) woman with a speaking role who's shown to have political power, and three (3) men with political ambitions and power.
Oh! Um, also every merchant selling goods or handling money is shown to be a man, and all the bankers and stewards mentioned in the book are men. (There's a couple of merchants explicitly identified as female who sell...poetry and history and pornography, but I trust I don't need to explain why this is Not the Matriarchy I'm looking for.)
How is this a matriarchy?
Good question! Men have 75% of the political power, and men are the guards and bankers and construction workers and explorers and tradesmen, and they can enter and leave the city with impunity, and women are singers and dancers and teachers and raise each other's kids, and a couple of them are scientists, and a couple of them are politicians, but mostly: they are actresses and teachers and homemakers.
This is not a Matriarchy, you're scowling. Where are the men crushed under the stiletto of oppression?
I knooooow, I tell you. Look, this is what Card thinks is a matriarchy: exactly the same as the US, circa mid 1980s, but only women are allowed to own residential property inside the city proper, there's a special religious lake that men aren't allowed to visit, and people sign marriage contracts with each other that only last one year.
(ONLY HETERO MARRIAGE. So basically: no-fault divorce is legal, but marriage is still only one man, one women, and gays are still icky, and there is DEFINITELY only two natural genders - which, by the way, is presumably why every man in the book spends 80% of his time panicking about whether he is Manning the Right Way, haha, lil sarcasm for you there - and no one is ever transgender.)
Oh oh! There are "wilders" - naked desert women who wander into Matriarchy City, where the women of Matriarchy City consider them holy and sacred, but ...it is so common for men to rape them in the street that there's slang phrases that have developed to describe the act.
Your Evil Oppressive Matriarchy, folks! Tremble at all of this sexy Male Oppression, y'know?
So there's that trainwreck.
Look, just...it needs an EDITOR so badly. Like all of Card's work, our protagonist is a boy whose one weakness is that he is Too Smart, right? So when we're in his head, it is generally acknowledged that his observations and perceptions are correct. There's a line in this book where the protagonist seriously considers who is "better," the "brutal but rational men, or the irrational but gentle women," when he's comparing their styles of worship.
SPOILERS: in this book, women worship by going down to their sacred lake, jumping in the water, and tripping balls. Their magic computer gives them hallucinations, but only in that lake.
In this book, men worship by going into a fountain and tearing themselves up with barbed rings. Everyone bleeds into the same water.
It is apparently considered pious to submerge your freshly-wounded body in this mix of god-knows-how-many-men's-blood and water*. Why? WHO THE FUCK KNOWS? The only rational explanation is "because otherwise how will you be SURE that everyone has the same amount of hep C and HIV?" but I don't...think that's what Card was going for.
But remember! Men: brutal, rational, (ALL INFECTED WITH EVERY SINGLE DISEASE). Women: gentle, irrational, (AND YET NOT THE ONES WHO ARE GOING TO WIPE OUT THE ENTIRE POPULATION WITH A HARDY STRAIN OF SYPHILIS.)
I could continue picking out the stupid bits - this is a city that doesn't have wagons because wheels are forbidden, and the city is not DIRECTLY on the coast, but somehow shark fights that take place in pools inside the side are big enough that they're a commonly accepted cultural practice.
(No, really. These people carry their goods in caravans on camelback. Explain in detail how you would transport a shark from the ocean to the shark pool without a wagon or wheeled conveyance of some fucking kind.)
The whole book is like this! Maddening, weird, nonsensical bits that don't fit with anything else that Card has told us about this world that he's building. It's a promising first draft from an aspiring writer who's not bad but needs a lot of technical guidance? But not really worth money, honestly.
*this practice is first seen through the eyes of the (probably?) fourteen-year-old protagonist, while he's naked, waist deep in a "swirling, thick mix" of other men's blood and water". there might be a way to interpret this that does not make you want to call Chris Hansen. good luck; i haven't found it.