The article addresses this. Unfortunately the "teachers" were being paid mostly just to be strong opponents for the "students". So AI ruins their market.
From the article: "the Go school recruits a professional player, who would agree to play a fixed number of games, like five games, one per week, at a certain price.... Of course there is still room for lower level classes and teaching, but pros are often better at playing teaching games than explaining easy concepts."
From the article: "the Go school recruits a professional player, who would agree to play a fixed number of games, like five games, one per week, at a certain price.... Of course there is still room for lower level classes and teaching, but pros are often better at playing teaching games than explaining easy concepts."