Just having a look now.
I've managed to compile NNCP on OpenBSD 7.5 (amd64), bit leery about it defining an unprotected call to `sendmail` though… seems if I deploy this on a server with a mail server configured, this is a recipe for relaying mail from unauthorised users to the public Internet.
So I think the concept is good, but we need to move carefully rather than rushing implementation.