Some client is going to be created that scans all known relays and request deletion.

Basically the opposite of what https://nostrsync.live/ does. 

 https://delete.nostr.com

https://nostr-delete.vercel.app

Already exists, and has been available for a long while. 🐶🐾🫡 

 Excellent ... I'll add them to my extensive list of NOSTR apps.