I joined this group so that one day, when time permits, I might be
able to go through the messages and what not to learn more about
syndication. If you don't think there's any worthwhile information,
then by all means, pull the plug.

My recommendation would be to open up the message viewing to the
public without requiring membership, place a note on the home page
that the existing messages are being saved for reference purposes, for
a while longer at least.