"the silence is deafening.
there appears to be no logic to the criteria collectors use for collecting songs at all."

Myself and others have attempted to explain the logic to the criteria collectors use for collecting songs. You seem bound and determined not to understand. So after a while, it does seem pointless to respond.

That being so, I will reiterate a few final points:

You have argued that folklorists refused to record original compositions from traditional singers - pointedly false, and easily refuted. American folklorists have recorded such songs extensively, and posts above demonstrate that UK folklorists have also recorded original compositions from traditional singers (perhaps not to the degree that Americans have, but that is only my impression based upon limited information).

You seem outraged that a folklorist would prefer to collect a particular song from a traditional singer over a 'better' version sung by a revivalist. Again - feeling like a broken record - a folklorist with the opportunity to record someone who learned ballads, songs or tunes from family, co-workers, friends, etc. within an oral tradition will certainly prefer to record said musician/singer over someone such as myself, who learned 98% of his repertoire from recordings, printed sources, etc. I can always learn new songs, new styles, etc. and I'm relatively young, but died-in-the-wool traditional singers are a far rarer breed.   Please refer to my chamomile reference above.

You seem to see no difference between an original song composed by a traditional singer and an original song composed by a revivalist. As Jim suggested above, the first will reflect the tradition within which the singer learned and developed his craft, and is a manifestation of that tradition. It is an animal of a different sort than the second. That being said, posts above demonstrate that folklorists have collected original songs from revivalists, so what are you grousing about?