EVEN IF most companies do inefficient things around race as a factor in hiring, at the top or lower positions, we have so many corps competing that best practices tend to evolve by natural selection in the system.

Do you agree with this argument as well? If not, why not?

I agree corporations will tend to do the more economic thing around race. If many otherwise qualified whites won't work a companies where blacks have anytthing other than the most menial jobs, and the society is 85% white, then the economic thing to do is to keep your job pool high by not hiring blacks into the jobs that would drive whites out of your job pool. The other economic thing to do is to pay blacks a market wage, where the market wage may have been driven down by the oversupply of blacks for the limited job categories they can be hired in to without comproomising access to the much larger white hiring pool.

"Don't buy stock in companies because companies are a local optimum." A nice little homage to the OP, don''t you think? Companies in a racist society will optimize their return with the actual society as a condition constraining the optimum. They are litereally not in the business of operating in the world as it should be or might be or you want it to be, they literally are in the business of operating in the world as it is.