@gibby From that source it seems that it helps significantly for about half, not so much for the other half. I don’t think we can just blankety look at the acceptance rates and say that since they are similar there is no significant help. Affirmative Action was put into place for a reason. URM’s make up a much larger percentage of the lower class socioeconomic’s than they do the overall US population, and there is a definite correlation between the social class that a student comes from and the chances that that applicant has to get into a top university, meaning that overall the average non-URM applicant probably has a superior application to the URM for these schools. That would explain why some schools that claim to have banned Affirmative Action, a good example from the link you provided is Cal Berkley, have an overall lower acceptance rates for URM’s than non’URM’s. While the acceptance rates between URM’s and non-URM’s may be similar for some schools, that still does not mean that there wasn’t some sort of significant boost to the URM applicants.
I personally would implement a affirmative action program to help the lower socioeconomic classes rather than the current affirmative action programs in place.