"One would be "Folk is anything down with an acoustic guitar with limited amplification by drippy hippies and stuff like that" (and one's mind boggles)."

To most peeps, I think that *is* what "folk" means - and that's precisely why traditional song has been effectively lost beneath the term. It's certainly what 'folk' has always meant to me (I wasn't around during the 60's when the revival was buzzing and hip). I'm not a muso, but I've always been interested in and open to different types of music too - which is just as well, because without exploring Sean Nos and stumbling into E. Trads somehow en route, I'd have never known that this vast body of traditional material existed beneath the genre of pretty boys and girls playing acoustic guitar and singing sad pretty songs about other pretty boys and girls that I'd been ignoring all my life. Arguably, the revival spawned a monster child - a very pretty and pleasant one, but it's smothering it's mother.