you were no longer guaranteed hearing a folk song at a folk club

There you go again, Jim. Putting an unsubstantiated claim across as fact. Give us details of these folk clubs where you can no longer hear any folk music and people may start to believe you. Until then I will make it clear that it is just your opinion.

and academic definitions are not the point in question. You said so yourself.

Subject: RE: the uk folk revival in 2019
From: Jim Carroll - PM
Date: 11 Oct 19 - 08:52 AM

...
As a singer, I have a loose definition that makes sure that people who turn up to hear folk songs will hear them or songs based on folk syles
...
My need for a tighter definition comes when I am writing or talking about the songs, especially as I am now interested in them as our social history carriers

Now, are you really going to "leave us to it" this time or are you going to make any positive contribution to the discussion?