In gender-imbalanced dating markets, the over-represented gender becomes increasingly more desperate in its dating strategies, due to lack of success. Desperation hurts honesty and worsens the signal-to-noise ratio.

When men are over-represented, true, women in general will find it easier to arrange dates. But those dates will, in general, be of lesser quality when men feel increasingly pressured to actively mask their flaws, in an attempt to stand out from other men in the dating market. Women then require more time, on average, to parse a potential partner's true personality and intentions, and develop trust. Requiring more time to develop trust raises the true cost for women of giving an individual suitor a chance.

(note: the prior paragraph is gendered because of context, but it also applies vice-versa in dating markets where women are over-represented compared to men, e.g. New York).