What do you do? Realistically you give them both what they ask and pay them unfairly. Congratulations, you're now part of the problem.
[1] Yeah, one is a dude.
Ultimately, the only alternative is to pay people equally. Which won't fly generally, as companies always want to pay the minimum amount that can keep the employee from leaving.
The fun thing about making a straw-man is you make yourself immune from criticism. I can't attack this point without having to completely define someone who is "pro-diversity" (what's that even mean?), and give evidence that no one in that group has the traits you claim of ("look at this feminist, see I was right!").
More importantly, what's even your point if this straw-man were true? I could just as easily say this about anything.
"Oh your life is shitty? Well I bet you wouldn't complain if things were working out well." It's an interesting case of vacuous truth!
The argument is to make things better for the people who have it worse at the moment, correcting for previous inertia. In this case, the inertia is that men were previously paid more or gained an initial advantage that allowed them to be paid more, and then that advantage has percolated across their various positions until the difference becomes more stark all because as you say "companies always want to pay the minimum amount that can keep the employee from leaving". If that's the case, then if companies could pay women less for the same work, why wouldn't they? Similar arguments apply to affirmative action and similar programs. That's the argument at least, whether I agree with it is an entirely different question.
What irks me is you dismissing the argument with your little straw-man and moving on to "the only alternative". You completely disregarded the points of everyone opposite the aisle of you in the most condescending way.
Find me someone (anyone, anywhere) who defends (even in the abstract!) a situation where women are paid more than men for the same work. That's a horrific strawman, and it tells me that you're looking at this as a war (with feminists as your "enemies" I guess) instead of a problem.
And no, you don't have to pay people equally. You have to pay them fairly. If there differences between individuals, that's fine. If there are systemic differences between easily classified groups of individuals, that's discrimination.
Isn't that their very argument?
Their point is a few need to be paid more even if they don't work for it, to make up for what is lost.
They are asking for inequality by very argument. Equality by their definition would be injustice to them.