Geoffrey Miller, Oliver Traldi, Spencer Case, and Bo Winegard in Quillette:
Is moral expertise possible? Well, we certainly act like it is in our everyday judgments of other people. We judge some people as lacking moral expertise, insofar as we don’t expect very good moral decision-making from them, we don’t seek out their advice on moral issues, and we don’t praise them as moral role models. Such people include young children, low-IQ adults, older adults with dementia, and criminal psychopaths.
We don’t hold our toddlers to the same moral standards as we hold our teenagers, and we don’t expect as much from our teens as we do from our work colleagues. Moral expertise develops gradually in humans, and parents take pride in any moral levelling-up that they see in their kids. In some people, moral expertise never fully develops.