Because private institutions want students to experience diversity. They don't want 20,000 Asian/White tennis and violin players who had enough tutoring from their parents $$ to get a 2400 on the SAT. People don't get this, diversity is a key part to the establishment of a successful learning institution. Studies have shown more gender/ethnic/age diversity has led to teams achieving more and problem solving more efficiently. source
What this is also doing is off setting a past injustice done that made it an unlevel playing field. There are a plethora of studies that show how many blacks are turned away due to their race despite having better/equal qualifications to their white counterparts.
Here is a study:
https://www.pnas.org/doi/10.1073/pnas.0403723101
Conclusion: Groups of diverse problem solvers can outperform groups of high-ability problem solvers.
Here is a whole book about how and why diversity benefits STEM:
https://www.amazon.com/Difference-Diversity-Creates-Schools-Societies/dp/0691138540
And here is an interesting article in Scientific America that answers your question and is where I found the book.
https://blogs.scientificamerican.com/voices/diversity-in-stem-what-it-is-and-why-it-matters/
>When we consider scientific research as group problem-solving, instead of the unveiling of individual brilliance, diversity becomes key to excellence. In his book, The Difference, Professor Scott Page lays out a mathematical rationale and logic for diversity. He shows that, when trying to solve complex problems (i.e., the sort of thing scientists are paid to do), progress often results from diverse perspectives. That is, the ability to see the problem differently, not simply “being smart,” often is the key to a breakthrough. As a result, when groups of intelligent individuals are working to solve hard problems, the diversity of the problem solvers matters more than their individual ability. Thus, diversity is not distinct from enhancing overall quality–it is integral to achieving it.
And finally, I remember when an automatic soap dispenser didnt recognize anyone with dark skin. It went viral fairly quickly because it was an amusing way to show people that diversity matters, which includes racial diversity, for if there had been someone on the team with dark skin, the team probably would have realized the problem before it was manufactured and sold.
https://gizmodo.com/why-cant-this-soap-dispenser-identify-dark-skin-1797931773
https://www.amazon.com/Difference-Diversity-Creates-Schools-Societies/dp/0691138540
Tell him he should read this book