@Leadbottom: you are adopting a very broad definition of folk music here, which appears to be something along the lines of "music of the people" - any music with a grassroots base.

You wouldn't be the first to have proposed this but I don't think it's workable myself - because it potentially includes all music. If it includes bedroom singer-songwriters, as you suggest, then it would have to include pretty much everyone who now makes music on soundcloud: popstars like Lily Allen and Billy Eilish, teenage techno producers and YouTubers.

If a definition of 'folk' expands to include any music made in a 'folkloric' fashion - any music so long as it has a 'from the ground up' beginning, then I don't see its usefulness because it is not specific enough.

Rappers, reggae singers and punk rockers do not describe themselves as folk musicians. The impetus to explode the definition of folk music seems to be unilateral: you never hear people asking "why shouldn't the definition of hip-hop be expanded to include people like Martin Carthy?"