Certainly the end of more strong marriages and two parent households
Women really need to reel it in at least to early 90s mores
And men? No need to reel it in?
The problem is, with all this debauchery, STDs have mutated and become much more virulent than they were back in the post-Puritan, pre-Pill days. So the old ways of married women, to keep the marriage together, looking the other way if their husband strayed occasionally, have now become a situation of Russian Roulette.
Both sexes must return to Biblical morality if they want to have stable families with neither of the parents dying of AIDs or crawling with syphilis or herpes (which is transmitted to the infant through the birth canal). Cheating and jealously also cause a significant number of injuries and murders every year.
And serial monogamy is horrible for kids. I think you and I may have posted before about "mommy's boyfriend" being the most dangerous person in a child's life, putting minors at risk for sex abuse and murder.