It's because schools want to retain a measure of control over who they let in. A true merit based admissions system (say min SAT score + lottery after that) is uncheatable and therefore schools have _zero_ control on who they have to accept.
The only reason why Harvard has kept its mythos of being the incubator of the next ruling class is because, well, they accept the children of the current one. Those are most likely to become part of the next ruling class by virtue of having been born into it. It's an old boys club. There's no intrinsic property of Harvard that turns them into this incubator.
And from the other side you have the brain dead equity idiots who are also against true merit systems, for equally twisted, but different reasons.
We're merely discussing whether certain things are used as inputs to a very complicated decision process.
Test scores are no longer being used as inputs in many places, in the name of equity: but I think almost anything you'll weigh higher will favor class, instead.
They're also removing race. And legacy status. The net effect is an admissions landscape that will look very different.
The only reason why Harvard has kept its mythos of being the incubator of the next ruling class is because, well, they accept the children of the current one. Those are most likely to become part of the next ruling class by virtue of having been born into it. It's an old boys club. There's no intrinsic property of Harvard that turns them into this incubator.
And from the other side you have the brain dead equity idiots who are also against true merit systems, for equally twisted, but different reasons.