Many organizations assume that if they achieve racial or ethnic diversity, they will also achieve viewpoint diversity.
Which is not correct.
Examine a diverse department of sociology at a large university and try to find a political conservative.
Viewpoint diversity itself is not always desirable. You don't want frequent dissent when it comes to ethics and legal compliance. There are many areas, however, where getting other perspectives is very valuable and may even be an essential ingredient in the organization's success.
If you want those fresh perspectives, you'll have to search for them.