Because the different outcomes of those groups is popularly used as a reason that there must be racism causing it which leads to division, hate, and further racist government actions as people imagine that that racism must be very serious to cause such serious effects. But it might actually not be very significant if the cause is something else. And such efforts won't even help the people who are suffering from poverty either. It would be OK if this was a niche opinion but it's incredibly widespread and actually has real world consequences.