Harvard (and other Ivies) repurposed a mechanism originally introduced by Yale to keep Jews out in the 1930s. If those Asian candidates had not been excluded using the arbitrary and capricious "personal" rating, it's mostly Caucasians who would have been displaced, not African-Americans or Hispanics.

The personal rating differs widely between the admissions committee and the the alumni volunteers (who give Asians roughly the same ratings as other groups). This happens for no other ethnic group. This is the smoking gun for racial discrimination.