If have been following this thread with a mild interest.
The main thrust seems to be that an activity is dying/dies unless there is a massive public interest in watching it.
I beg to differ.
The watching public is of little interest to the health of any activity, except for producers and the like, who then have the opportunity to make obscene amounts of money.
What makes for the health of an activity is, instead, the number of people
doing it, that is, engaged in a commited way to that activity.]
Often one hears the idea that unless people listen to a certain repertory, it will disappear. This is not true. A piece disappears form the repertory not when the general public loses interest in it, but when performers stopped playing it. As long as a performer keeps playing it, the piece will remain in the repertory. (e.g., Alkan came back to the repertory not because the public demanded it, but because performers like Hamelin decided unilaterally to play it).
This is true for everything. Is ice-skating dying? Just because there is less public interest in it than, say, football, does not mean that it is dying, since there are enough people
doing it to sustain the activity. And no amount of public interest will keep football alive if no one wants to
play it anymore, no matter ow much people may want to
watch it.
The martial arts are a very good example of this sort of thing. There is a huge industry devoted to martial arts – and until the advent of martial arts movies – completely sustained by people wishing to learn it and practise it. In fact due to a tradition of secrecy, public displays for the general public entertainment (like in boxing and more recently in the Olympics) were non-existent (and some traditionalists – me included – would argued that transforming the martial arts in a “sport” for public consumption is what will eventually kill it).
Often Victorian times are quoted as one of the great ages of piano, not because everyone was going to concerts, but because everyone was playing it (there was no TV, radio or computers, and it was deemed a desirable social skill and a husband catcher activity).
Engaging in an activity privately is far less visible than being a passive watcher. The true health of music is not going to be ascertained by how many people go to concerts, or even by how many CDs are sold, but rather by how many pianos are sold, and how many music scores are produced or even by the number of members of pianostreet. Considering these three indicators, I would say that classical music is doing fine.
And so is collecting stamps.

Best wishes,
Bernhard.