Explain how innately asymmetrical sexuality is good for either side in the first place, whether or not it’s natural. And even if paedophilia/hebephilia is natural, that’s not the same as it being insuperable. What do you see insane about full parity between a male and female partner (or two male or two female, just to be sure), anyway?
Markedly older male than female wasn’t an ancient norm, anyway. Peloponnesian War Greece expected men to do a couple of decades in military and combat before marrying, and younger wives were just how to minimize childbirth fatalities. (I get the impression Greece didn’t put much stock in romantic love. Exceptions existed—there’s a hypothesis I’ve heard that the real reason Sokrates was fine with Xanthippe was that he simply genuinely adored, in modern terms, the tsundere mentality, and Euripides’s “Andromeda” apparently had some resonance—but still not really omnipresent.) Medieval France, as best as I can tell, forbade noble heirs to marry until after their father’s death, so they would likely be 30 or even 40 on accession…and they again wanted to minimize childbirth death. Compare, however, to Israel/Judea, where similar-age betrothals were the norm—not much place for romance when the deal might be made when the heirs were children, but it looks like the Hebrews weren’t keen on May-December matchups everywhere.
But the general concern always seems to be “she should produce children without dying”, and the state of medicine then translated that to relatively young motherhood on average. But with widespread medicinal advances, we can actually wait for the woman’s mental maturity to catch up with her bodily maturity when needed.
Even if I strongly suspect Berge doesn’t have a high opinion of any kind of mental maturity, male included…