Nostr is much more than a social feed. It's the most known use case, but it wasn't invented to compete with social media. Have a look into this talk I gave at Bitcoin Conference Ireland this year, you'll see that Nostr is more of an identity protocol for the internet: https://www.youtube.com/watch?v=02l1vZWEgjI&list=PLrWmNjlKQ7qj8BvFpvqfSwOoDsouiplm2&index=13