> how much of the difference between them is romantic connotations associated with the 'real thing'?

Plenty. I'd say the words "connotations" and "associations" in general account for every bit of the substantive (i.e., non-microscopic) difference.

A person who knows nothing about rustic pots, like me, would declare them to be "obviously" identical.

But if I were told (truthfully or otherwise) that one was a fake/counterfeit/imitation, I would value it less, or not at all, even while appreciating the skill of the faker/emulator.

Is the famous version of "Edward" a "folk ballad"? The question can be a red herring. What's interesting are matters such as the formal and thematic qualities of "Edward," the degree of somebody's editing (if any), how and where (if we care) it was obtained, what it resembles, who (if anybody) likes to sing or recite it, how much of its history or background can be discovered, and innumerable other questions of human interest - to people who are interested in them.

The 1954 definition describes a real phenomenon, an identifiable kind of music and song. Other kinds of music and song are other kinds. So what?

That says nothing about their quality or value.

Whether a piece can be fit (or be forced to fit) the '54 definition doesn't affect the definition's accuracy as a description of an identifiable category.

All such fitting does, it seems to me, is affirm that the fitter likes to think of the piece as "folk" - for whatever connotations and associations that may have for him.

Researchers, listeners, and performers will all go their own way.

The play's the thing.