I agree entirely with what's been said here though it's worth remembering that not long after the startup of the revival the music industry latched on to the idea that there might be a few bob in it fpr them and some of these clubs were outcomes of that
For me, when the money boys lost interest the scene found its own level and began to call the shots for itself
For me, that led to the real Golden Age of folk song, with singers deciding for themselves what was worth singing
My first experience of live music was in The Cavern in Liverpool where you could hear some of the finest jazz in Britain

The same as I described on the folk scene happened to Jazz - a discovery, a brief period of comercialisation and a leveling out
By the time I got to London at the end of the sixties I could sit in 'New Merlin's Cave' in Mount Pleasant and listen to Bruce Turner and Humph in comfort until my hair stood on end with pleasure
Good days
Jim Carroll