Your OP is well aware of the distinctions between the 2 categories in his heading. In Britain and some other English-speaking places they are labels applied by researchers and revivalists simply to distinguish between those singers who were collected FROM who were not part of either of the Revivals, and those who were part of one of the Revivals, writing their own material and singing songs supplied by the first group. There is no quality factor implied in any of this. Both parties can be respected for what they have done and what they do.