Obviously, girls are most attractive and fertile in the twenties. If you look at the economics of it, it makes the most sense for them to lock in the best husband possible during that time (and preferably one that is 10-20 years older than her). Because it will become ever harder to find a good man with each passing year.
But these days, most women women, even "smart" women, don't do this. Instead, they sleep around with Chad(s) in their twenties (Chads = Hunky playboys who have no intention of marrying anyone). Then, in their early 30s, the Chads stop paying attention to them and they finally realize they've hit The Wall. It is at that point that they settle for someone well short of their "ideal" man.
The really shrewd women don't give it away (e.g., keep a zero or low body count) and find a high quality man to marry in their 20s. If they do this, they've usually optimized their economic outcome. A girl who lets a man "take care of her" during her prime years is selling herself way short, even if she walks away with a hefty cash settlement.
I've shared this opinion with several young female relatives of mine (in a subtle way). All have called a mysogynist. They just can't handle the truth.