I don’t think I said anything about “adding” it in recent years.
You asked why people are questioning NU’s admissions practices specifically, not the Ivies. This is what I am responding to.
The Ivies and peers do not offer both EA and ED, it is one or the other, again with the U Chicago exception which explicitly started offering both (not recently…recency does not matter for my point) as part of a program to increase its image compared to what it considered (rightly, IMHO) peer institutions by increasing applications, thus lowering the admissions rate, and increasing yield.
That is exactly my point. NU should NOT be viewed as a safety school anymore for anyone but it is still going into admissions with the mentality that it is a safety, or at least a back-up, for the students it wants to attend. And this mentality means there will be a lot of high stats students that NU actually would want who will pay their fee and get deferred…not because NU genuinely wants to compare them to the RD pool, but because they don’t want to accept students who will ultimately get into a preferred choice and not enroll. Thus, yield protection.
If NU offered only ED, like Brown, Columbia, etc., or REA, like Stanford, Yale, Harvard, Princeton, Caltech, it’s application numbers would go down.
If NU offered only EA, its yield rate would go down.
The Ivies accept the students they want and do not focus anywhere near as much on yield protection. Harvard assumes if you are applying, especially early, even though it is non-binding, that they are among your top choices, probably your first choice.