There is a phenomenon, particularly in large metropolitan cities, where women who earn more money and have acquired advanced education believe they deserve a higher value man because of it. Many 35-40+ women fall in this camp. Their education and earnings go up with age (these women have masters, law degrees, probably earning at or near the 95th percentile+), while their fertility and beauty deteriorates. For men, the upper echelons (lets say the 1% top earners) have their pick of women, and they generally want younger women, as they don't care about the women's earnings. So it's difficult for these women to find suitable partners where they can feel that they are marrying "up". It's a big thing in the black community in the US, where black women are becoming highly educated and high earners, but only 1 in 4 black women will marry in their lifetimes. I suspect that whites and other races are starting to follow this trend. One thing I have learned is that if you are ever dating a woman and she feels she could do better than you, the relationship is doomed.
Yupp.. that has led to more living alone more than ever, and huge demand for frozen eggs because they want to preserve their special eggs for the 'High' value male. Because in their mind, at 33, the men they know are still boys and they're going to be patient because they know they deserve 'better'.
Little do they realize, even if you don't have mind right by 32, the probability of meeting the right person goes 'down' bigly, and having a child naturally goes down with it even more.
In the mean time, every year, a whole new crop of younger women enter the field. By the time a women really sees and feels it, she's in her late 30s usually. Well, a really successful guy at around that age, is going to go for low 30s. But they'll have their pickins really because as noted, that same low 30s woman is extremely discriminatory against the last of the regular suitable mates in her age range as she wants that older super successful type guy. So 1 out of some big number his the jackpot. Then a bunch of women in that low 30s hold out because that 1 person they know did it, why can't they.
And as a guy just over 40, I can say, not matter what, just from raw nature, a women once she hits that late 30s, somehow, that natural appeal for goes down. And yes, men are physical and there is this 'deflated' feel, even to girls a guy thought was hot and wanted to get with even up until mid/early 30s. I'm sure inherently, men can feel the lowered quality of eggs in a women near 40 and just generally, fundamentally less attracted, especially against an early 30s woman.