Since 1993, there appeared several other lists on the
extropian and transhumanist topics, and a number of people
went there. (see my list of lists at
http://www.lucifer.com/~sasha/lists.html ). There has been massive development of extropian and transhumanist websites since then as well, so people have alternative means of expressing themselves and obtaining the materials.
Some people are only on extropian-select, or transhuman, or polymath lists. I personally receive all, but do not have much time, especially for arguing the basics.
A few hundred people is all a mailing list as a structure can bear. I am not even advertising or listing my Lists page for the fear that it can topple the discussion groups.
If you want to have an active discussion forum with thousands of people you have to do something special.
Did I ever mention filtering, alternative private moderators, or anything like that?
If we spent half as much time on active promoting of extropianism as we spend on debating issues, we would have taken over the Net by now. At this point, I rarely bother to share the proposals even, nobody wants to work anyway (please tell me if I am wrong).
Do we want to make a social impact, or we just want to chat?