A better way to say it is that they're looking to produce the most successful 22+ year olds, in a mix that perpetuates the schools' power, wealth, and intellect

A better way to say it is that they're looking to produce the most successful 22+ year olds, in a mix that perpetuates the schools' power, wealth, and intellectual prestige. That means admitting some of the smartest 18-year-olds, as well as some 18-year-olds who will be successful because of family wealth and social connections, and then giving them an environment where they can further expand their intellectual and social advantages to get even further ahead of their peers.