in which aunt BeaN beats a dead horse

I actually woke up thinking about this this a.m., so I'm going to type it out so I can get it out of my head.  But I'm having a really hard time figuring out how to make my point.

So.  Try this.  Let's say you tell a group of older women that women in their twenties are more attractive to men than women in their fifties.  You lay out the biological reasons why this is (supposedly) true:  women in their twenties are potential producers of children, so on average they are more attractive because their ability to attract men ensures the survival of the species.  After most of your group of older women cringe inwardly and think, "Oh, God, I know, I know" (kidding), there are the following reactions.  One goes out and gets plastic surgery and starves herself into oblivion and manages to look ten or fifteen years younger than she is.  One goes out and finds a dozen gorgeous 50-year-olds and a dozen unattractive 25-year-olds, lines them up, and says, "SEE? It's not true."  Another takes the opposite tack and searches (to the ends of the earth) for the five men on the planet who think older women are more attractive than younger women. (kidding!  kidding!)  One finds a 50-year-old woman who is having a baby and says, "See?  Your point about the biology is wrong."  But one of them says, "So what?   Maybe it's true, but I'm happier now than I was when I was 25, I take better care of myself, and I like the way I look.  Big deal."  And she ignores the whole thing and walks out.

So which one has done the most to subvert the cultural bias about women's attractiveness?  The last one, of course.  At the very least, she's the happiest and most content of the lot.  The others are all consciously or unconsciously shoring up the idea that it matters whether or not older or younger women are more attractive.  And that's how this argument (the one from the previous post) feels to me.  We feminists, when we argue so vociferously that there is no biological basis for the cultural differences between the genders, are unconsciously shoring up the idea that those differences are important, that it matters that men are (or are not) stronger or taller than women beyond the bare statement of the fact.  OK, so (usually) men are stronger than women.  That has no bearing on anything outside of a situation where physical strength makes a difference.  Like when I need help to lift a cooler full of drinks and ice into the back of my car. :-)

???  let me know what you think.  I'm pretty sure there's a hole in my logic here somewhere but it's escaping me at the moment.