I'm not sure why this, of all things, is a problem. "Forced monogamy" means "not polygamy." In other words, enforced monogamy is a remedy for the problem of natural power hierarchies that he talks about-- where only the very top members of a species get almost all the resources-- including access to mating privileges.
It's pretty straightforward-- if each man can marry only one woman (and not more), then there will be more available females, and more men will have a chance to have a life mate. Otherwise, billionaires will have thousands of wives and offspring, and normal Joes on the street are going to be left with nothing but porn and a bottle of lotion.
It's pretty straightforward-- if each man can marry only one woman (and not more), then there will be more available females, and more men will have a chance to have a life mate. Otherwise, billionaires will have thousands of wives and offspring, and normal Joes on the street are going to be left with nothing but porn and a bottle of lotion.