Just because that's the specific focus in the article doesn't mean that the point is so narrow. Just as it's incorrect to suppose that a sci fi story gives us a useful picture of how society would be transformed by certain technologies, it's also a mistake to conclude, for instance, that a story about a bunch of young boys stranded on an island who devolve into barbarism is a useful case study in human nature. The contents of the book never happened, it's just something someone imagined, and to the extent that the author's belief that such a thing might happen constitutes evidence, we can do better by looking at what reasons a person would have to believe it in the first place.

Any novel whose experience could be replicated via the process I described would be a bad novel, but what you'd be leaving out would not actually be evidence for the truth of the points the novel is contending.