Bill --- So sad to pick up your recent e-mail, expressing your view of the active participation of all those on your mailing list. It sounds like a very sad indictment of many members.
Having regard to the fact that 'you' are the central and pivotal 'activist' working on our behalf, every mail sent in any direction, gives you work to do. I am not personally computer-knowledgeable enough, to know what sort of workload you have to deal with. But, is it possible, that people don't send e-mails because of loading you up with work. ? Just a thought. !
If, on the other hand, your main concern is the fact that not enough people are:-

(a) Sending in recorded songs.

or

(b) That not enough people are expressing what they feel about these songs, and/or, not showing any gratitude.
it's a different can of worms. !

I can fully appreciate how you feel, but, it has occured to me Bill, that there may be an aspect of the matter, which you 'might' have overlooked. !! Which is:-

That many of us who do receive e-mailed thanks and comments from others, immediately strike up an ongoing e-mail rapport with such people, 'WHICH YOU MIGHT NEVER GET TO HEAR OF'. !!! I have personally received many e-mails which come into this category, and I have little doubt that others do so.

As I see it, the expressed gratitude of people, is either posted onto the forum (in which case you know about it), or done privately, in which case you might not get to hear of it.

Nonetheless, I have little doubt that all memmbers will understand precisely why you feel as you do, and hopefully (for our sakes) the situation will improve, by virtue of increased 'consideration' for the efforts of others. -- NB:- having said all this, I personally have been over the moon with the amount of comment I've received. T'would be a crying shame if it all collapses. - Colin