Even if it weren't, the charitable assumption to make is that the critic interpreted the comment correctly.
I have to agree with komponisto on this one. If the downvoter understood the comment and still voted down then he, or she, is a twit.
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.
If you know more Eliezer Yudkowsky facts, post them in the comments.