I think an enlightened approach that eschews a single, network-wide policy on the acceptability of anonymous messages in favor of leaving it up to the individual email recipient is something that we could sell to the Internet as a whole.
It would help if there existed some filter software that automatically installed itself in a user's .forward and filter out anonymous posts (and nothing else). Such a tool should be written in nothing more than shell scripts and grep, for the absolute widest in portability. (Not even perl, which, believe it or not, is not yet universally available.) Were such a utility posted to alt.sources, and if all a user had to do was ftp it from an archive, unpack it, and run it once, we would be in a much better position politically, (even if the utility received very little use). It is difficult to install mail filters. Our argument for user filtering would be much stronger if installation were simple. A similar argument holds for anonymous posting filters in a global KILL file. Eric