Not to state the obvious, but an upper-middle class white guy reared in the suburbs is shaped by his experiences, carries certain assumptions, and views the world through a particular prism as much as a working-glass Puerto Rican gal from Queens, or, for that matter, the half-black son of a single mom raised in Hawaii. The person belonging to the cultural/ethnic/religious/gender/racial demographic that has traditionally dominated a field (and thus whose perspective has long been the default) may not have given as much thought to his prism as a member of a non-dominant group. But that does not make his prism a neutral one. It simply allows him to more freely indulge his delusions of pure rationality and objectivity.
This is ridiculous. It's just a coincidence that opposition to affirmative action comes almost exclusively from white men. Nothing to do with background at all. Right, Rush?