However, the diversity of men may be limited (e.g. they are all software engineers...). It would be like going to Baskin-Robbins and all they had was various types of strawberry ice cream.
When you go back to the ice cream shop to demand some kind of control over what kind of ice cream flavors end up in your cone, the shop-owner apologizes and reveals that the reason why the other flavors are at random is because he doesn't actually scoop the ice cream, the giant ice cream cones actually arrive like that from the factory, and although 70% of the cones do come with some claims about which flavors are inside, 60% of those claims turn out to be false, so nobody pays attention to the label, and anyway here's another giant cone, maybe this one will turn out great and really be "your kind" of cone.
https://www.salon.com/2016/02/07/the_guys_who_wont_hear_no_m...
http://www.theonion.com/article/romantic-comedy-behavior-get...
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).
This sounds to me like nothing so much as confirmation bias. I've lived in SF for six years now, and gone on dozens of first (and far fewer, but still nonzero, subsequent) dates. While I do see some slight evidence for this notion, it's the exception, not the rule, in my experience.
That is to say, "the plural of anecdote is not data."
I'm curious about how an excess of men can hurt women in the dating market.