Sure there will be some sort of interest into the future - maybe the majority outside the UK? But the "scene" as we know it now just wont be there.
At the nighters and soul nights I go to (Burnley, Lifeline, Rugby, Tadcaster etc) the majority of people are in their late 40s and upwards. There are some younger ones but a definate minority, so how can anyone think that in 10-20 years time the numbers attending venues wont have shrunk drastically?
Any new blood wont be in sufficient numbers to balance the people getting too old and dying away(literally, sad but a fact!)
I agree with Dave Abbott, the same scenario will apply to collecting - there will be "some" collectors but nowhere near as many as there are now and consequently prices will have to drop.
Get out and enjoy yourself while you still can and anyone who views their collection as an investment should think seriously about selling up