I don’t fall into the technical people description, but I think I heard nostr:npub1zuuajd7u3sx8xu92yav9jwxpr839cs0kc3q6t56vd5u9q033xmhsk6c2uc explaining how followers are checked on nostr - basically something scrolls every npub on the relays you are connected to see who has followed you to generate that list. Seems not super efficient 🤷🏼‍♀️