Since you ask. I suppose I could wheel it out again:

'The tradition' comprises art forms of a distinctive national, ethnic or social group rooted in that community's lore and customs and passed on orally, aurally or by demonstration rather than by written/recorded or formal didactic means. It has thus belonged collectively to that community, rather than to individuals or the state, and tells the history of the people from their common experience.

In the case of music, its platform has been predominantly the informal social gathering, the workplace or the home rather than the theatrical stage or concert hall, and pieces tended to be known by what or who they were about rather than by composer. This is not, of course, to say that trad musicians have not borrowed and adapted from formal composers or from other cultures. Obviously they have, and do, which is why the tradition continues to evolve.

However, three factors in the current revival are forcing ever more rapid and inexorable changes:

(a) digital archiving
(b) writing, consciously, 'in the tradition' and registering the result with MCPS/ PRS
(c) population mobility resulting in monumental cross cultural influence and collaboration.

It will, thus, never be the same again. 'The tradition' will remain that static body of information that has been quite literally passed down before the irrevocably altered times put an end to the centuries-old process (cue Richard Thompson . . . ). What is NOT traditional, by definition, is a recently composition of known origin. Even if you call it The White Hare.