Good though, Charlie.

I recall once looking for information on "Sir James the Rose" (a song by Steeleye Span). The library had over 5 million books in the collection, and one of the librarians was quick to take me by the arm and guide me to the relevant section. He knew the folk/history section very well, and he was insistent that I come get him if I was stymied in my pursuit. Turns out he was an avid 'folkie'. (But, for instance is not proof and one robin doth not a Spring make). I'd guess that if your premise is true, it might be because there is so much folk available, music that has history. And whether one likes folk or not, it seems evident to me anyway that the lyrics sure beat the snot outta most other kinds of music lyrics for meaning and purpose. IMO, of course.