There is an established published definition from 2014. Musket published it on Mudcat...

But don't worry, he isn't precious about it.

The point is, folk as a term is not defined by any 1954, 2014 or any other convention. it is what it is marketed as. It is what people see it as.

Musically, the two unfortunate descriptor terms "traditional" and "contemporary" have been bandied around for so many years, they have provenance of their own. It is impossible to say "folk" and just mean one of them.

McColl wrote folk songs. I have no issue with that. Neither do millions of others. (Once whilst interviewing Fred Jordan, I quizzed him over a song he "collected." he said the final few verses were his own work, as the words to what he learned weren't any good....)