Returning for a moment to the topic (please mods don't delete his one), here's what Steve Roud, a scholar I respect greatly, has to say about Fakesong, and 'mediation' in particular, in Folk Song in England. It does concur in many respects with what I’ve been trying to say here, though I should add that it’s a while since I read it and it did not inspire directly my contributions.

[p 8]
"... this new academic promise was soured by negative polemic from some quarters, which still reverberates strongly in the field, and has also been perpetuated by those from outside our field who, seeking a general understanding of the subject, have been deliberately misdirected.

This negativity became the new orthodoxy, and the early collectors came under fire from all sides. Their motives were questioned, their honesty impugned, their editorial practices dissected and found wanting, and their collecting and publishing rebranded as ‘mediation’, which although technically a neutral word is always used in a negative sense. Their theories (or assumptions) about the songs were rubbished, and they stood accused of misrepresenting and misappropriating the working classes and their culture. All their claims for the importance of folk song were denied because they were based on flase principles and selective vision. Above all they were found guilty of being ‘bourgeois’, and acing entirely within the frame of, and in the interests of, heir own class. Following this line of argument, ‘folk song’ was declared never to have existed...”

[p 177]
“What we got was facile bourgeois-bashing... the bourgeoisie had invented the whole notion of ‘folk song’ for heir own purposes... the new orthodoxy... is only now showing signs of losing its grip. he tendency is mentioned many times in this book, precisely because it was influential and cannot be ignored, though it must be refuted.”