It's a controversial topic. #amethyst recently added support for note editing/forking by creating a history of note versions like wiki edits.

I personally dislike the idea of mutable events on nostr, preferring history to be set in stone. It isn't even technically possible because once a note is on a relay, the relay operator is in no way obligated to delete it, modify it or even keep it indefinitely.

But clients can implement note edit history like Amethyst and show the latest version by default, which creates a network split where some users will see the edited version and others, on other clients, will see the original. This was inevitable and we'll see how it plays out.