...unless you don't know who your relays are... which is true for most people right now.

Relay operators can close their relay at anytime.

Same for image/video servers.

AND

...unless your app developer or signer app developer goes nuts and makes deletion events to all of your posts and publishes them all without your authorization.

Nostr still needs plenty of trust between players.

Delegating that trust to third parties just adds another rug pull operator.