Lacking empathy is a defect of the mind I would say, and clarity refers to the whole of it, just like health refers to all of it. A person who has healthy fingernails but has cancer isn't healthy, and a person that excels at specific technial problems, but isn't even bad, but completely absent, when it comes to other very basic ones, isn't brilliant.

> morality is highly subjective

And the word "brilliant" is not? "Highly" is just padding: Morality is subjective, and so is everything else, ultimately. It's not a magically different kind of thing to think about, it's just one of the more basic ones.

https://en.wikipedia.org/wiki/Moral_reasoning