I don’t think anyone knows that. I work in an environment where, hit the 750 and you satisfy. In the end, they may choose more with higher scores, but that’s the bar. If a legacy presents with, say, 700s, nothing assures that they get a bye. In fact, during the working reviews (several layers of that,) legacies, URMs, etc, are not in separate cohorts or piles. (Yes, they are coded as such, but not separate efforts. And sure, in the end they may lighten up a little on legacies, then. But underqualified is underqualified and the goal is kids who can thrive.)
But I find CC info often confusing, sometimes misleading. When Brown, P, Dart and Stanford, at various points, showed the number of applicants in stats tiers, the vast majority were rejected. 90%+. A 1600 and/or 4.0 kid is not rejected simply because he’s not hooked and so his bar shifts upward. The non stats portions are crucial.
So when a kid does have the stats strengths and rigor, they are still subject to the rest of holistic.
When one says, re: grades and strength of curriculum, that, “It’s the most important, there’s probably not even a close second,” so much of holistic is missed. You have to have the range and rigor of ECs, the quality of thinking, awareness of the college/your match to all they look for, and much more.