> This article is directly talking about Japanese pure literature,

No it isn't, did you even read it? It mentions animes as well, not all of the works mentioned are books.

Makato Shinkai’s She and Her Cat is an anime, not a book, for example.

Edit: They adapted that anime to a book, but a book adapted from an anime is hardly "pure literature", it is definitely pop literature.

The article is referring to the recently released book and calls She and Her Cat a book the only two times it references it.