Don't solve a problem that doesn't exist.
Usenet access is readily and economically available.
There are
enough providers that there are sites that review which is best.
Google for 'usenet providers' and see for yourself.
The idea of course (at least I think) wasn't to provide generic usenet access
on AMPRNet. Instead, it would be used for closed access discussion like this
mailing list. Only a couple of hamradio related groups.
Of course this immediately shows the practical problem: the authentication of
valid users. You would need to maintain a table of users similar to what the
mailing list now has, and when you want a couple of news servers around the
world, you would want this access information to be somehow synchronized between
them.
Additionally, you may want some groups accessible to "any radio amateur".
But then you run into the problem that has been encountered so often: how to
authenticate a radio amateur without maintaining yet another user list where
new applicants have to be validated by people who would prefer to do more
valued work.
Rob