> without central authority over who could connect to the network or firm control over groups and their contents
Moderation. In public forums, everything else is trivial and moderation is the invisible stinking hairy elephant in the room. To the question "why isn't there a decentralized open protocol free software X" the answer is moderation. Think or it as the discreet but efficient bouncers without which a sufficiently popular public place cannot maintain a welcoming atmosphere. Newsgroups became sufficiently popular, death by inadequate moderation ensued.
Moderation. In public forums, everything else is trivial and moderation is the invisible stinking hairy elephant in the room. To the question "why isn't there a decentralized open protocol free software X" the answer is moderation. Think or it as the discreet but efficient bouncers without which a sufficiently popular public place cannot maintain a welcoming atmosphere. Newsgroups became sufficiently popular, death by inadequate moderation ensued.