I think the argument is the opposite... they start with one or more orders of magnitude of qualified applicants in excess of capacity. and to meet DEI goals, only X% of those accepted can be white anyway. how they actually pick from the qualified applicant pool is fairly arbitrary to begin with. so as long as whatever on-campus KPIs they track for the legacy-admit population are the same, why does it really matter?

I was not personally a legacy admit to my college (so no skin in the game really), but fwiw I don't think it's an entirely illegitimate thing to select for. most schools have their own distinct culture and consider that an important thing to preserve. I imagine families that try to send their children to a specific school over multiple generations probably feel a stronger connection to that school than the typical graduate, so putting a thumb on the scale to help them seems like an approach that could work.

if anything, I'm more upset about how recruiting for college sports works.