I know this will be seen as misogynistic, but it's far from the intention: in at least one latin american country (so it can possibly be just a matter of that society) office drama is kept in check while there is <50% of women in the office (percentage taken out of my posterior). Above that the amount of backstabbing and mean gossiping going around makes the places unbearable to work in. And this is not something I've seen only myself, as my female friends have independently made comments about this.
Of course, I encourage equal opportunities, but there are some weird social interactions depending on the group's composition. This can be seen in male predominating places as well, which can be just as toxic (if not more) to somebody who doesn't look like the rest. I'm just pointing that hiring women is not all happiness all around, because hiring people is not happiness all around.
I guess it comes down to homogeneity, in the same way you can claim there is no racism in countries with low inmigration and no heterogeneous population.
Women in charge are usually much better at playing office politics, and I mean this as one of the highest of praises in an office setting. Being able to navigate through all the bullshit while keeping sane is precisely what somebody in a big company needs. I'm reminded of George Carlin's comment on God: "I'm convinced that if there is a god. It must be a man, because looking at the state of things, no woman would have fucked up so badly."
So no, hiring young, attractive women and not promoting is completely backwards. You hire women that you will promote, because they are so much better at leading.
That being said, all generalisations are wrong. I've met women and men alike that have been backstabbing misanthropes, but believing that men and women are equals is like denying that Dutch people are tall, or that I'm not too short to reach the top drawer at my house. That's why you have specialisation, I won't play basketball and it is unlikely there is a Dutch jockey. If you are hiring and thinking from the beginning in terms of men or women you are missing the real value of that person, which may or may not align with your precognitions.
EDIT: got the joke wrong (first "woman" is "man")