Are you referring to the lawsuit where they pledged not to consider finances in the admission process then did it anyway?
No, I understood "legacy applicant" refers to the children of past students. And they get priority access, not having to earn their own way.
Call it nepotism, or preserving privileged, it seems wrong.
The finances thing is trickier, where they would prefer people who can pay. The cost of education in the US is insane, and a massive barrier to equality or meritocracy. But is there any reason to tie that to "legacy".