This is an answer based on my own interpretation of Aishes Chayil, so take it for what it's worth.
I am a woman. I have always felt that Aishes Chayil was deliberately written with women as the intended audience. (Not saying it was or it wasn't actually written for women, just that it reads that way in a certain sense.) What I mean is that it focuses on aspects of the woman's experience that could be appreciated by other women, and it highlights rewards that have currency for all women.
In regards to the first point, Aishes Chayil describes the woman's own experience, not just her results. It doesn't just say "She always has food ready on time"; it says, "She arises while it is yet nighttime and gives food to her household." We hear about how she "seeks out wool and linen" and "girds her loins with strength" and "envisions a field and buys it." All of these are parts of the woman's own story. They are little details ofher daily life, small things she does and sacrifices she makes that often go unappreciated. But in Aishes Chayil, they are brought out into the light and lauded.
This is not only important because it sets the record straight and helps men appreciate the women in their lives, nor only because it makes women feel good to be praised for their efforts. It's also key because it gives women the sense that this song is really speaking to them. And this is achieved by pointing out details that ordinarily would be apparent only to the woman herself--in a way, by assuming her point of view.
The fact that Aishes Chayil speaks to women by speaking as if a woman can also explain the passage about her husband in the gates. Perhaps this is an example of the Torah getting as close to chick lit as it ever does. We are reading about all the nice things this woman has--"Her entire household is clothed with scarlet wool. Luxurious bedspreads she made herself, linen and purple wool are her clothing. Her husband is known in the gates when he sits with the elders of the land. She makes [cloaks] to sell..." Perfect, right? She has beautiful clothes and an elegant home; her husband is important; and she runs an Etsy store. What more could a woman want? And why else would these hypothetical "nice things" be listed than because they are what women want?
It's her song, her time, and her moment of pleasure at the beginning of Shabbos. That's why it is allowed to be so "superficial" (although of course it's not, since ruchniusdik and gashmiusdik pleasures come together, on Shabbos as in life).
So why do we hear that her husband is well-known in the gates? Because Aishes Chayil isn't only a praise of her--it's written for her. ...For her to hear, and for her to enjoy while she hears it.
P.S.: There is possibly another note of female empowerment and pleasure in the overturning of the husband-in-the-gates passage by the last two lines of the song, which state "Give her the fruits of her hand/and let her be praised in the gates by her very own deeds."
In that light, the original lines about the husband can almost be seen as a setup for this final, fierce coup.