Web of Trust could be the basis of significant efficiency and social connectivity for improvements for nostr relays. Currently relays do not relay to each other. Instead users must post to multiple relays with the hope other users sharing the same relay will see it. The discoverability situation is already tenuous: e.g. I see users who share just one common relay out of my 17. This has long-term scaling implications because many-to-many connections do not scale.

Web of Trust could form a backbone to know which notes are safe to replicate between the relays. That would improve discoverability for a lot of people without every user needing to share the same relays.