>>4
>>3
Nostr actually looks pretty neat on the surface level. It's like a distilled AP, and relatively simple. A similar thing happens on some of the RSS aggregator servers that run tinytinyrss <https://tt-rss.org/> since users can "share" RSS articles that other users can subscribe to. The content gets copied around to multiple servers.
Unlike Nostr though it has no identity magic (though you *could* shove it into a non-standard XML tag on Atom) but you can dedupe using source domain + id.