I base this on a single scientific fact. Most of the men who ever lived (pre-historically before agriculture) never reproduced, whereas most women did. One common estimate or interpretation of the genetic data is 80% women / 40% men.

We know this because there are biological markers indicating twice as many women as men were responsible for contributing to our ancestry or dna. However in the modern era 81% of men reproduce, so clearly things have changed since then, and the only explanations are social and economic.

As agriculture began to form, we abandoned our hunter-gatherer ways in favor of mass production of food which can be stored and reliably feed a growing population without the need to be constantly migrating from place to place or fighting with other humans over hunting limited animals for the protein needed to form and fuel our larger brains. This immediately lead to class division, which also lead to an extraordinary concentration of wealth in a few men's hands, financial and sexual wealth though.

Indeed, we see that in some cases 17 women were reproducing for every single man. This obviously didn't go on for too long. Religions were developed, which still preaches 1 man 1 woman marriage as the only moral choice sanctioned by God himself. And it's obvious why people felt the need to impose these rules when the sexual reproduction ratio gets that badly out of balance as it did. That will obviously have negative social consequences if most of the men are excluded from a basic biological function we all desire.

This was basically a concession that was first made by the growing human elite class in favor of the common man or pleb to maintain order and keep building more advanced civilizations which will continue to benefit the elites. To do that you need to pay a man a fair wage which enables him to support himself and his family. And you need a social framework in place to avoid unequal distribution of sexual wealth, which enables elites to retain their financial wealth for the most part and not be murdered like they were in the French Revolution. This is what elites fear most.

But none of this changes the natural state of man, that most of us are simply not that desirable on our own merit. We need social institutions that value marriage and 1 man and 1 woman. These are lies, fundamentally working against our tendencies, but they are effective, proven ways of making human progress. Our jealous nature is also compatible with this framework, so it is not completely incompatible either, it's just our tendency absent other influences.

Sources:

Genetic evidence for unequal effective population sizes of human females and males.

8,000 YEARS AGO, 17 WOMEN REPRODUCED FOR EVERY ONE MAN

Humanity Has More Mothers Than Fathers, DNA Reveals