"I am not sure, mind you, CS, that no traditional songs will ever more be writ [in the sense you have just used this phrase]."

The folk revival has become a form of tradition in and of itself (though tiny by comparison), so the term of course may be applied in various ways - but the culture that forged those particular old songs is simply gone. The industrial revolution ended it and we are left with a specific body of cultural artifacts which give us a glimpse into the imaginal worlds and experiences of them as wot went before. But still, I've absolutely no idea what it must have been like to live then, to think then, to partake in that world. However much I might like to imagine it, or engage with those songs that were preserved - it's another country to me, and ever will be. As for 'traditional songs' in today's world, then I'd probably put my money on stuff like Abba and the Beatles: we all know the words, everyone can sing them. They'll probably go down in history in some fashion and people in a couple of hundred years time will look back at the hey-day of pop and maybe even have societies for the preservation of traditional pop music?