What happens today when you visit a broken web URL? Do users panic and stop using the internet? No, they give up, or they complain to the people who sent them the URL, sometimes users rely on third party services to find the missing content in some other URL or archive or cache, and then they reshare the updated URL.

All these things would work for broken Nostr event links. We could do much better, by providing more context and streamlining the process, but we shouldn't create a million obstacles to prevent people from understanding what is happening.