/////First-position fiddle does two octaves and a third, flutes and whistles about the same using only basic technique. Range doesn't have anything to do with intonation////

To be honest, I have not paid very close attentio0n to what you write because I don't understand it. I don't know anything about the styles of music you are referring to. I don't even know what "traditional" actually means--apparently, whatever you say it means. But was the octave they used 2:1? If so, then it is tempered. An untempered octave is something like 2.0273:1 if memory serves me correctly. If they were tempering, then they were attempting, with at least some degree of success, 12-TET.

////In case you hadn't noticed, traditional music has not died out, and traditional fiddlers (anywhere, any idiom) don't care about the circle of fifths. And mouth organ manufacturers manage to shift millions of instruments tuned in some sort of meantone every yea///

Since they are trying to stay true to this "tradition" you speak of--I suppose they wouldn't care about the circle of 5ths in the same sense that the Amish don't care about muscle cars or smartphones. But since I and just about everybody here don't have any desire to live as anachronisms, why are you discussing it? In short, I don't have even the tiniest idea of what you are talking about. And I'm hoping that you will make the connection that all the people who have an interest in the subject matter of this thread feel no differently than I do.