Do you mean to say that diversity of ideas is promoted by hiring the same kind of dude in the same kind of role all the time?

Besides, "diversity of ideas" is not the point. There is no such thing in the industry anyway (see "Uber for X" or "Facebook for Y" etc). The point of what I suggest above, essentialy imposing a quota to "help" companies hire more of the kind of people they currently don't, is to give more opportunities to those groups, not to help companies increase their bottom line.

Because increasing companies' bottom line is a goal of companies, not a goal of society. Society must ensure that all its members are treated fairly and have equal opportunities (an opinion, of course and you may disagree). Whether company Z makes a few more bucks or not is of no consequence, as long as the whole community prospers together.

And there's no way for the whole community to prosper together when half of it (at best) is traditionally excluded from the best paid jobs.

Edit: also, from my POV as a soft eng, the idea of using only half of your resources (in this case, people) because you are unwilling to challenge some centuries-old tradition that says the other half is not as good, is bloody stupid and very, very inefficient. It's up there with forcing left-handed kids to learn to write with their right hand because the left one is "bad". Or something.