I think the inverse is better: Post to just 1 place, your "outbox". Read from the "outboxes" of the people you follow. See NIP-65. You'll end up reading events only once (or twice or three times, at ...
Vast majority won't want to/have the knowledge to manually manage up and down relays based on a changing follow list and each npub in the follow list also changing the relays that they're interacting with. Sounds exhausting. Unless I'm missing something?
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