In his autobiography Keith Richards says he reckons recorded music was THE big thing of the last 100 or so years. Whether one agrees with him is a different question, but we are lucky in that, thanks to the recordings made from the Victorian era pioneers onwards, a huge canon of traditional melodies exists in recorded form as well as in notation.
To be clear here, I assume the discussion concerns the melodies themselves, not arrangements, instrumentation or lyrics.
Ultimately it doesn’t matter what individuals choose to do with them then since the source material remains.
I think it was Norma Waterson who said when she wanted to do a song she’d listen to as many different versions as she could find so that she could do it differently, which I think’s great policy.
I’ve played in tune sessions where other players have been able to tell where someone’s from by their use of accidentals, phrasings etc. At the other end of the spectrum I’ve witnessed sessions where the tunes have been note for note, phrase for phrase, copied slavishly from records. Joe Public didn’t know, or mind.
The only important thing is to keep playing them, anyone who gets hooked will sooner or later ask the question Chris Coe always used to: “Where did you get that one from ?” And then, “Where did they get it from ?”