" how has folk music become so insular, and music of folkies?

I would imagine it is a direct correlate of the growth of mass commercial media supported by advertising. And to some degree it is still the music of folk, but a lot of 'folk' are being left out of the loop because they have been drawn in to hypnotic mass media (e.g., TV) instead of being exposed to people who play or sing and still appear to be people rather than commercial entities.

A