"Merit" as I understand it—who can best perform the job—has almost never been the primary hiring characteristic. Companies are comprised of people and those people are almost always the ones making the ultimate decisions. In hiring, this means that "merit" almost always means something different or is a secondary consideration behind more personal factors. "Is diverse" doesn't really strike me as inherently more corrupt a trait than "went to the same school I did" or "is a member of the same country club I am," though why it gets a lot more attention is certainly not a mystery.