Seems like an inefficiency, to have to keep everyone's delete events forever. Even this change wouldn't completely solve for that, as some people are rotating fast through keys or auto-deleting on a script, but not "burning" the npub.
Maybe we should make more use of NIP-40. If someone is delete-happy, couldn't they just have a client setting that causes their notes to expire after about 3 months. Then you don't have to retain an event, after deleting.

GitHub
nips/40.md at master ยท nostr-protocol/nips
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