It will be indeed as "objective" as what medicine/biology defines someone "healthy". That being said, we already define certain categories when it comes to disabilities, and with very few disputes. Moral values could also be like that, and indeed its like that for who are legally called psychopaths and such.

Anyway, I think the author of the article linked in the root comment is looking for something more divine for moral values, but as a disappointment, just repeats the same rituals of thousand year old fallacies like as if theist believes have objective basis from which other objective basis can be inferred.