WoT is the biggest benefit. Closeness analysis within the set of engagement among npubs via events. There's potential to create very powerful tools form curating the content you see within that set. Algorithms built on a neo4j cache will be more powerful because they are graph native.

But the other major innovation would be to improve notifications because relationships between events become bi-directional when they're cached in the database.

Which means that if Event A references Event B, the owner of event B doesn't need to query all notes that may contain links back to them, but rather just look for outgoing relationships from Event B. And Neo4j can do that magnitudes faster than any other database.