If you don't agree with that, I'd love to hear why, and why the related studies are false. Can start with this one, which is the first result: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.685...
There's quite the bibliography to pour through there, though, if you really want to shatter the science behind why diversity is a good thing. Good luck!
We can be pretty confident that if 50% of the population are women then 50% of the best candidates for a given job, by natural aptitude, are women. The same logic applies to minorities as well, so we can be confident that any process calibrated to finding the best person for the job is going to turn up a diverse workforce.
However, once policies designed to enforce diversity come in to play, that correlation will be broken and you just have a sexist/racist/whatever hiring system.
What would be the motivation to induce or somehow encourage males to take up a career for which they clearly have no particular enthusiasm. I wonder how many males harbour a secret desire to be a nurse but are discouraged by societal norms? Need some amazing evidence for that one.
Pretty sure more males harbour a secret desire to be a nurse than males that harbour a secret desire to be a garbage man, and yet we see nurses are 90% female and garbage men being 90% male. The question is why.
You shouldn't be as confident as you're probably wrong. Women have on average better verbal intelligence, and men have on average better spacial intelligence. So we can be confident there are jobs where either men or women are more likely to be best candidates.
And even then you can't reasonably claim that most jobs are better performed by spatial or verbal thinking. Both tend to have their moments.