The business case for diversity, theorizes that in a global marketplace, a company that employs a diverse workforce both men and women, people of many generations, people from ethnically and racially diverse backgrounds etc that has a more limited range of employee demographics.
An additional corollary suggests that a company that supports the diversity of its workforce can also improve employee satisfaction, productivity and retention. This portion of the business case, often referred to as inclusion, relates to how an organization utilizes its various relevant diversities.
If a workforce is diverse, but the employer takes little or no advantage of that breadth of that experience, then it cannot monetize whatever benefits background diversity might offer. In most cases, US employers are prohibited by federal and state laws from giving race or ethnicity any consideration in hiring or assigning employees.
However, the US Supreme Court has upheld the use of limited preferences based on race, ethnicity, and sex, when there is a manifest imbalance in a traditionally segregated job category. Better able to understand the demographics of it serves and is thus better equipped to thrive in that marketplace than a company.