Something just occurred to me, which isn't directly related to the original article, but is I believe relevant to the debate that ensued around it. Apart from any ethical, social and economical considerations, one of the easiest arguments to make against sexism is that even from the point of view of pure self-interest it is plain stupid. Passing on a perfectly qualified candidate because of what's between their legs (assuming that's not directly relevant to the position in question) is completely irrational and self-sabotaging.
While there may be high quality studies proving a preferable distribution of certain relevant traits in men or women, that information gives you at best some minimally higher chance that if you were to pick someone at random from the group with the better distribution they might be slightly more capable in that one particular way, maybe, which may or may not result in a higher qualification for the position depending on countless other factors and their combination or interaction with the trait in question. In other words it's completely worthless compared to the much more precise and specific information that you can gather from directly evaluating the individual in front of you.
Here's a thought experiment on the topic of enforced diversity. Disclaimer - I'm pulling the numbers out of the air and they aren't relevant. The example is also a little contrived for the sake of argument, I'm just trying to illustrate a principle.
Let's say we have a medical university that admits 100 candidates. The admission tests are administered and evaluated blindly, the professionals responsible for the evaluation aren't aware of anyone's gender, ethnicity, age, looks, they don't have any information beyond the content of the tests. They have also undergone bias awareness training, just in case, because why not.
The 500 candidates who apply are ranked according to their test results. In addition to these anti-bias measures, the university has a diversity goal of admitting 50% women (medicine is probably not the best example for this, but bear with me here). Now whether the enforcement of those goals is written in stone or strongly recommended with whatever pressure/incentives behind it, the result is quotas.
As it happens, for whatever mix of reasons, genetical, prenatal, environmental or social, at this particular time in this particular place only 40% of the top 100 happen to be women. The diversity goals however dictate that 50% must be admitted, so 10 men will be refused admission in favor of ten less qualified women. Let's say for the sake of argument that they all graduate successfully.
And now let's say I have to undergo a medical procedure and pick a doctor. I know for a fact that all 10 doctors available to me have been to the very same university. Not being an MD myself and not having any recommendations, I am in no position to judge their qualifications, so all I have to rely on is gut feeling and metadata. And I know for a fact that there's a higher chance that a female doctor from that university has been admitted on quotas instead of skill and I'd know that chance is higher even without the information how many women were in the top 100 because of the very possibility which does not exist for men. And now I end up in a position where gender mainstreaming and diversity efforts, in particular quotas, somehow managed to make sexism a reasonable, rational basis for making a decision, which wouldn't have occurred to me in a thousand years.
Without quotas, I have no good reason to care about my doctor's genitals or the color of their skin. With them I just might.
If that's not shooting yourself in the foot, I don't know what is.