I think the essential part of this thread describes the popularization of the folk song style in popular music. These are the "marketable" folk-like songs that are associated with particular artists. This is a big problem. Today it's difficult to separate the two.

The next question is "essential" for who? Certainly not for the traditional singer who is a carrier of a specific culture.

I think a better title would have been "100 most essential folk-like pop songs".

Frank