I suggest that unless the clubs cease to allow themselves to be used as musical landfill sites, and unless what goes on there is performed to a basic standard, they will die.

I doubt it, actually. I think what's far more likely is that clubs will flourish as "musical landfill sites" - I could name two local examples, both of which pack them in week after week. Quality is quite variable and anything goes in terms of material, but in its own terms it works. The audience consists mainly of performers and friends of performers; everyone who wants to can get up and do a turn; and at the end of the night somebody a bit more polished does a few numbers, and everyone goes home happy.

What you won't hear a lot of, at either of those folk clubs, is anything traditional. From my own experience, I'd agree with you that folk music in folk clubs is in a poor state (although it's doing quite nicely at a couple of local singarounds). But the clubs themselves seem to be flourishing.