"'What is Folk?' is another way of asking 'Who Are We?' for some people."

Absolutely right and IMO, most unfortunate. It's only one step from the provenance of a song to the lineage of an individual or society. Nothing else can explain the dogged pursuit of the 'authentic', as though it will deliver the musical mother lode of 'the people'.
The truth is we're abstracted from those songs in so many ways that any attempt to live them out is doomed to failure. We can interpret them as best we can but projecting anything else onto the music is comic at best and dangerously misplaced at worst.

If 'the' tradition was seen as 'a' tradition without the accompanying verisimilitude hokum and guru racket accompaniment, we'd have a far more vibrant and inclusive folk 'scene'.