Anime may get people initially interested in Japanese, but the article fails to mention what happens to these people after they start taking the courses. You can go to any Japanese program in the USA and you'll probably find that 80% of the JAPA 111 (or whatever the course number) students are there because they're interested in anime.
But how many of those people come back the next semester? Not many. Once you get into the upper level Japanese classes, most students are either Asian themselves or they have some genuine interest in the language. As the years go on, the classes get smaller and smaller.
So while anime may attract a lot of students to the Japanese program, they're also instantly turned away. Don't ask me why that happens though. But I think a lot of it has to do with false expectations about the difficulty (e.g., "KONICHIWA! I can speak Japanese because I watch anime! Ja~ne bakayaro. Kawaii ne").