what I'm more saying is we need closed communities. yes decentralization, yes gossip/outbox etc. A melting pot is nice but we need closed communities to help encourage a focused & thematic discussion. 
Nostr groups are a mess and i argue the simplest implementation is select the relay(s) for a specific community you want to be in. Will UX be difficult? Maybe, but just like a feed where only posts with a single hashtag comes through, you can do the same for relays.
Always optional. Like a faucet, you & the relays choose what level of openness you want.

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