Follow is not enough. In a narrow sense, social media alone is not enough. The definition should be expanded somewhat. Like, Telegram and private chat groups on Signal are more 'social' than Nostr. Weblogs can be social too. They're even the first social media. Then think about email etc.
I don't see any sense in a standard that is narrowly confined to timeline-based platforms. However, as an independent, open format, it would make much more sense and would also be ready for the next big thing.
Private groups are coming to nostr. E2E encryption with no meta data leak. Already implemented in nostr:npub13myx4j0pp9uenpjjq68wdvqzywuwxfj64welu28mdvaku222mjtqzqv3qk . So … this would fit your bill?
https://github.com/nostr-protocol/nips/blob/master/44.md
Problem is… nostr would still need a user applied marker for “is trusted friend”, because metadata is not available for querying “the people you engage with privately”. Though… a smart client could offer user option to “mark trusted friends based on your private messages” or something.
As I said, I don't like the idea of a Nostr-centered implementation. It would be a shame to artificially limit something like that. "WOT" means more than just Nostr. And Nostr isn't the end-all, be-all of wisdom. One should look ahead when it comes to such an important standard.
