I don't even think ideological / philosophical / political diversity is that good a thing. If you are the college admissions person, are you more likely to admit a eugenicist who thinks their ethnic group is best? I mean, that's a really unusual opinion for a prospective student to express! Wouldn't that increase diversity? You work in a media company and someone who wants to bring their niche fundamentalist religious perspective to your content - whoa, super diverse, right? Hospital hiring a witch doctor? Don't have too many of those on staff!
I think for the vast majority of positions what you want is someone who can do the job well and their ability will naturally constrain their opinions and experience and, in some cases, their demographic characteristics as well. For students you want smart people who have a documented history of being able to learn. Intellectual diversity should arrive naturally from a population of smart people trying to learn. Intellectual diversity should not be a goal itself.
I think for the vast majority of positions what you want is someone who can do the job well and their ability will naturally constrain their opinions and experience and, in some cases, their demographic characteristics as well. For students you want smart people who have a documented history of being able to learn. Intellectual diversity should arrive naturally from a population of smart people trying to learn. Intellectual diversity should not be a goal itself.