Young, single guys don't like having all of their coworkers also be guys? (Especially if they work crazy hours and are a bit light on social skills.)

Having more women in the field would make it more socially acceptable?

A bigger industry is better? (What about the industries we'd be stealing the women from?)

More competition is better? (Even when you're the one being competed against?)

Maybe having more women is a sign that the industry has become socially acceptable, or that we've learned better social skills, or something?

Maybe "women" here is really a stand-in for some larger group that wants our perceived salaries without our perceived social sacrifices?

i.e., I suspect it's not really about the women at all...