Just opened a Damus iOS PR that mitigates reply spam with web of trust. After using this feature on my developer build for a few days, I can definitively say that my experience exploring Nostr is way better, and all reply guy spam gets sent down to the bottom of the thread and can be optionally hidden.

GitHub
Add web of trust reply sorting in threads to mitigate spam and add tips on what Trusted Network means by tyiu · Pull Request #3067 · damus-io/damus
Summary
Spammers can reply to threads that users are subscribed to, which pollute the view and reduce the amount of legitimate signal that they can...