The original reason was, like everything else in the “holistic” admissions system, to limit the number of Jews entering the Ivies and other “elite” colleges. They will not admit it, but it still fulfills the purpose of maintaining the social status quo of the college. Basically, it is there to make sure that the “right people” keep attending the college, with “the right people” meaning “the same type of people who attended during the last generation”.
Alumni tend to support this, even if their kids do not attend the college, since the reason that alumni tend to be engaged is that they had good experiences during college, and therefore, they prefer that the college look more or less the same as it did when they attended. For most people “the same” also means “the student body looks pretty similar to the one which was there when I attended”.
For some people “the same” means racially the same, for others, it’s gender ratios, and for others it’s all about socioeconomic class. It all depends on what bias these people bring with them, and what power structure they wish to maintain. There are also first-gen who rightfully want to finally benefit from the power structure which has kept their family on the outside until that point.
From the point of view of the colleges, it is, among other things, about increasing the involvement of the richest and most powerful people. As long as the rich and powerful feel that a university is “theirs”, they will support it. Entitled people will happily support the continuation of their entitlements.
Besides, every business knows that the best costumers are return costumers.
I’m pretty sure this post will be flamed, because there is little which angers entitled people as much as pointed out that they are entitled. Most people live under the illusion that they deserve everything they have, and hate when this illusion is shown to be an illusion…
@barrons “There is no reliable math to prove the 150 point boost theory.” That is because legacy advantage is not applied equally across all applicants.