Perhaps "making the charitable assumption" is, in general, too narrow a phrasing.

Often it happens that someone reveals themselves to be either a twit or a fool, or ignorant or evil, or stupid or mired in delusion and fallacies, etc. In such cases, different people have different intuitions about which state would be worse.

For my part, valuing intelligence, I'd rather be a spiteful contrarian than stupid, largely because people with that problem have higher upside.