There has been a lot of wise words already expressed on this thread and I empathise with all of them. BUT as a singer, collector, writer, editor, researcher I have a split personality. When I am wearing my singer's hat I agree with every opinion expressed here. Like everyone else I stamp my own personality on the songs I sing, in many ways. However when I'm wearing my researcher's hat I need to know if a song has or has not been deliberately fabricated/rewritten/collated by someone like Bert Lloyd or Ewan MacColl or Thomas Percy or Walter Scott or Robert Jamieson or Peter Buchan or Sabine Baring Gould, or even Jeannie Robertson or Duncan Williamson. There are other value judgments that are valid other than whether it is a good song or not.
Some people might not like this fact and they may not understand it, but they are entitled to their opinions.