First, I think it's interesting to put some error bars on the actual numbers. One, it's from the Post, so their pro "feminist" bias could skew toward narratives

First, I think it's interesting to put some error bars on the actual numbers. One, it's from the Post, so their pro "feminist" bias could skew toward narratives (Young men driving the decline in sex) that emphasize declining male potency. Two, this is "US people" so it's limited to one culture. Second, to explain the effect, I offer the following two theories: - degraded sexual endocrinology. Hormones are very important in arousal and libido so this is likely the biggest effect. - society punishing male sexuality. The low evidence standard (in the court of public opinion) to female fake accusers, creates substantial risk for men. Under this theory, the age group effect can be explained as bigger on the young, who are still forming their attitudes about sex and observing society's discourse, than on older people who came of age in a less risky era. It's unclear to me how "downregulating sex" by social / hormonal mechanisms is affected by the massive viewership of porn. The other most interesting theories I think are the economic ones (changing income), because sexual biology is intimately wired with resources seeking in our brains, in ways more pronounced for women than for men.