I don't have an opinion on either side really. There is a valid case for both. But nip09 is a _request_. Relays can choose to deny it or support it.
If users do or don't want that feature they can stay or leave. But if a user uses a relay that federates all it takes is a single even to leak to a relay that doesn't delete, or the user know it was leaked.
Client's just need to be forward about what "delete" actually is. It's a calm letter to a relay asking pretty please delete me. Which then also is federated (nip09) so every deletion event is also shared.
Ngl, probably a feature used to bully more users than it helps. Well see I guess.
