I'd like the ability to request delete those spam gift-wrapped messages, if they are addressed to my public key. I believe that requirement should be added to NIP-17 or NIP-9. Then I can write a filter to get rid of messages that I don't recognize and unwrapping.
Discussion
This would help. signing a NIP-9 delete event for gift wraps addressed to you.
It would be nice if relays accepted this but there is nothing stopping a client from accepting it and ignoring those messages