Jim hasn't been discussing "sessions" - he specifically has been talking about organisations which designate and publicise themselves as "Folk Clubs". How many "Folk Clubs" are there in your list ? It's certainly not 200.
I can only speak from my experiences in Scotland, but I would think there are fewer than half the "Folk Clubs" in Scotland at the moment than there was in the 1970s and 80s. I can also say from personal experience that when I was in a band playing clubs in the mid-1980s, the average audience would have between 40 and 60 in number. I played a lot of the Scottish clubs about 7-8 years ago as part of another group, the average number in the audience was 20 - 40. Average age would have been over 50.
These are my personal experiences of "the current [ or very recent ] state of folk music in Scotland" - which I accept does not necessarily extrapolate to the whole of the UK.
I have also returned tonight from a "singaround / session" at the Aberdeen branch of the TMSA. There were 25 people there. When we started the branch in the mid-1980s, we very rarely had less than 60 attending. Not a single soul there under the age of 40, maybe even 50. Figure it out for yourselves.