That was debunked: https://econjwatch.org/articles/mckinsey-s-diversity-matters...

Oh hey, a good faith argument. I thought about going and googling for more studies supporting my position, but I'm not sure if that actually has much of a point?

Maybe I can come up with a stronger/more defensible argument: creating a just and equitable society is valuable on multiple levels including moral and economic.

Societies without "lower classes" are good for a variety of reasons.

Researching into why we have lower classes and, hopefully fixing that, is a good thing for a bunch of reasons.

Something something how many potential new einsteins aren't pushing boundaries because they had to drop out of highschool and work 3 jobs?