I think Guest is missing the point in saying

“To me, Ariana Grande is folk music. Bohemian Rhapsody is folk. I define folk as whatever you can sing in a pub – and for people to be able to join in and be as shit as you like. "quote Eliza Carthy. EFDSS President
I disagree with a couple of things here.
1. it is not ok to be as shit as you like, it is important to perform to the best standard you can out of respect to an audience that has paid good money, and to show respect for your material

Yes, if you are a performer you should want to do your best. But is that 'folk'. I think she is making the point that folk is what people do. Join in with 'whiskey in the jar' at a pub singaround, or playing Winster Galop (at a trot) because it's the only tune you know. And people join in and raise the roof. Joy.
Personally I wouldn't want to fall over at the end of the evening, but I do appreciate an unjudging encouraging attitude. You can't be marvellous at everything, but that doesn't mean you don't get something out of it.