The latest thing to blame on gay men

This article on hookup culture in The Washington Post attributes today's hookup culture to demographics and states that

gender ratios within the LGBT community do affect different-sex dating, oddly enough. According to Gary Gates, a UCLA researcher and a leading expert on LGBT demographics, cities known for being LGBT-friendly (New York, Washington, Miami, etc.) have disproportionate numbers of gay men, but not of lesbians. Consequently, the different-sex dating markets in these cities are worse for women than the overall census numbers imply. DATE-ONOMICS illustrates that Manhattan’s hetero, college-grad, under-30 dating pool has three women for every two men — which, like it or not, is exactly the sort of sexual playground for men portrayed by Vanity Fair.

The argument for causation implicitly presupposes something not in evidence, namely, that the male dating pool is some sort of zero-sum game in which gay men displace straight men.