Overall better outcomes for children in two-parent households, directly reduces the number of young-ish listless males (large numbers tend to destabilize societ

Overall better outcomes for children in two-parent households, directly reduces the number of young-ish listless males (large numbers tend to destabilize societies), and makes it extremely clear who is the "next in line", so to speak, for a myriad of societal interactions in which a person becomes somehow incapacitated and needs individual assistance. In the case of two earners, it also significantly reduces risk in a world where most people are paid a single salary or wage rather than having many customers.