I can see where you’re coming from. My armchair hypothesis is that people aren’t being taught how to have healthy long term monogamous relationships and why being in one (a healthy ltmr) can be so amazing. I won’t speculate on the cause, beyond suggesting that there is a negatively correlated social trend (based on no actual data) that seems like a logical inference.

This hypothetical situation implies that it is much less likely for people to find another party interested in teaming up. Luckily if both sides: know how to identify a healthy ltmr, know how to & will participate in a healthy ltmr, will keep testing partners until a healthy ltmr is formed, and are balanced population size (and more), everyone interested and capable will end up in a healthy ltmr. The regressions in this scenario are longer expected time to relationship and the emotional cost of testing potential partners. (Probably significant enough to address).

Based on the above scenario actionable advice is to do one’s best to satisfy the assumptions, weather the regression costs, and try to optimize your strategy to minimize the costs (becareful not to become a bad actor/violate the assumptions).

This scenario & strategy is likely full of holes, but maybe it can provide hope that there is a strategy that offers a high success rate.