What shouldn't be underestimated is the sheer pleasure it gives some of us baiting 1954 protagonists. Is this pleasure hatred of our fellow man? Of course not, is the sheer pomposity of people who use the definition as a stick to beat singers they don't approve of while huddling close to the words to validate what they do. Whatever that might be.

The same people will be heard dismissing 'academic' readings of the definition in a 'we've got no time for that fancy white collar smartarse stuff' way, while simultaneously swatting away genuine enquiry like a Dickensian despot with an ignorant servant.
I've repeatedly pointed out the logical holes in 1954 but fans of the thing have a blind spot and it heals by the next thread. It's useless as more than the vaguest attempt to identify a tradition and seems to attracts bullies in its wake. If it were qualified by 'revival' in twenty foot high neon letters it may act as a signpost but does none of the things it says on the tin.
So in answer, a folk song is anything an informed person says it is.