Why not email groups? (also known as mailing lists)
Email groups are still actively used, provides pretty much same user experience usenet provides, can be decentralized (federated), easier to filter spam, can apply moderation (approve contributions before publishing) and all of us already use email for a reason or another.
Email groups are still actively used, provides pretty much same user experience usenet provides, can be decentralized (federated), easier to filter spam, can apply moderation (approve contributions before publishing) and all of us already use email for a reason or another.