My impression is that Metheny was simply telling the students that it will be more difficult than they might have imagined to play jazz for a living, because there is not much of a market for it in today's "culture". and that they will need to be strong and persevere.
The rest of the discussion here is somewhat off his point, I think.
I don't know that Metheny's point, if I have understood it correctly, is so radical. Richard Davis, the jazz professor at the University of Wisconsin, has been telling his jazz students for decades now that they have to be prepared to play all kinds of music, not only jazz, if they want to make a living in music, because the session opportunities which existed in the 1950s and 1960s have not been there for a long time. That hardly seems like a controversial idea.
Except for Metheny's emphasis on the words "hostile" and "culture" and "cult", he is making much the same point, I think.
I have read some of Metheny's other speeches and he does tend to go for dramatics, to emphasize a point with colorful or perhaps over-the-top language. Maybe that's what it takes to get through to an auditorium full of students, or what he imagines it takes. In my college teaching experience I have often wished I literally had some firecrackers to wake up some of the students while I was presenting material.