I thought I could resist getting into this, but old habits are strong...

The meaning of the word "Folk" depends upon what you're looking for. Folk music to a musicologist is something entirely different than Folk to a cultural Anthropologist. It's like arguing about whether a cow is a mammal, or a vertebrate or a device for converting grass to milk.

Incidentally, "Folk", to the Digital Tradition, is anything someone likes enough to bother copying down.