The fact that you immediately equated "diversity" to "lowering your hiring bar" and "under-performing" is as ignorant as it is insulting.
Women and brown people are not lower quality humans, and it has been shown over and over and over that companies who hire for diversity perform better.
Women and brown people are not lower quality humans, and it has been shown over and over and over that companies who hire for diversity perform better.
http://lmgtfy.com/?q=do+diverse+companies+perform+better