I would not put nip-65 into nip-01. I wholeheartedly agree with you that social networking is only a small part of what nostr can and will become.

But I do think there needs to be some advice about relay usage moreso than we have today, where clients fail to rendezvous and people try to fix that by blasting. Each use case will have potentially a different solution. I think inboxes and outboxes are general enough concepts to work in multiple use cases, but certainly not all, there are half a dozen use cases already that don't choose relays in that way (take nsec-bunker for example, or a livestream service, or relay-global feeds, etc).