Clubs dying?
If you define "folk club" strictly as the "booked guest every week" format then yes they are. When I first became interested in folk music in the late 60s there were four clubs meeting every week in my area, three booked a guest every week and one was a singers club with an open stage rather than singaround format. I never heard a pub session mentioned in the area at that time.

The same area now has three weekly and one monthly club with no more than occasional guests but there are a number of bar sessions and singarounds.

The end result seems far more introverted and less welcoming to strangers but judging by the posts here most people don't want to promote the music but prefer private little gatherings where nobody is bothered about their vocal shortcomings. Nothing wrong with that as long as you aren't promoting it as a public entertianment at the same time.