"Mr. Wroble sticks with and cites an application quotas as his predicted consequence of ... eliminating quotas."
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Neither part of that is true. He was addressing potential reactions of "Trump conservatives" to a merit-only admissions policy. 
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"Yet he doesn't offer us what could possibly be wrong with judging on merit."
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True, but irrelevant. He was speculating that the "White Nationalist" faction (like Sessions) of the "Trump Conservatives" would not like the logical consequences of merit-only admissions policies.