This is a little like the battle of the Clades in linguistic studies. When you have a big, dynamic field like language, there is always an impulse to subdivide it into groups of like thing, but the hook is that you have to choose the attributes you are using.

You could define the perpetration of unaccompanied CHild's ballads as "oral agrarian Anglo-Saxon pre-industrial" musical tradition, if you wanted. You could probably label it in historical terms, or by its scalings, or by its rhyming methods, or some other attribute.   Depending on how you chose the diagnostic attreibutes, you would find the set included more or less instances, and would include and exclude different candidates. The first definition would rule out, for example, many of the Appalachian versions of the same songs, even though also agrarian, oral, and unaccompanied.

It would be a lot more useful for purposes of discussion if we chose labels we could relate to that could actually be used to define the set of candidates we were discussing, instead of miasmic generalizations that are, essentially, semantically null at worst or impossibly ambiguous at best.