You really think that unbiased data for an issue as complex and multi-layered as this is possible? There is never going to be a paper that proves once and for a

You really think that unbiased data for an issue as complex and multi-layered as this is possible? There is never going to be a paper that proves once and for all that the best people to hire are white american males. So don't talk about "we need the data" for situations where it is clear that there will never be any data. In such cases, just do what you feel is the right thing: if you feel your business will only do well with a particular type of person, stick with that type of person. Personally, I found the argument as constructed convincing - intellectual diversity is neccessary. And a homogenous crowd is not likely to be intellectually diverse.