Yes, I do tend toward (I wouldn't put it more strongly, as my take on it could be altered by a well thought out counter argument) the closed trad (it has to be, IF oral transmission is the criterion).

Narrowing the discussion, this would give each country its own body of traditional music, in every case the one word descriptor "Traditional" would be good and sufficient to the needs of identification.

As I said above, this leaves the general descriptor Folk free for broader use.

I like the elegant simplicity of the family tree model of grouping under the folk banner, and cannot see the justification, or indeed the need for inventing new descriptors.

It would be entirely logical IMO for all non trad to be considered contemporary, as this represents only the output of a single century. I am sure that, whether WE like it or not, with the passage of time, the best of that output will become recognised as some form of "Tradition Part 2". The rest deservedly will fade away to be replaced by 21st century contemporary, and so on ad infinitum.

Thank you for your kind response to my attribution comment, it is much appreciated.

Don T.