It is worth noting that due to endpoint key escrow on by default in the non-e2ee iCloud Backup, iMessage is already presently broken and not e2ee as Apple has e

It is worth noting that due to endpoint key escrow on by default in the non-e2ee iCloud Backup, iMessage is already presently broken and not e2ee as Apple has endpoint keys available to them to decrypt almost all iMessages that transit the service (Messages in iCloud) in realtime. Even if you enable iCloud backup E2EE, or disable iCloud entirely, iMessage is still not E2EE as your conversation partners are escrowing (to Apple) the keys from the other endpoint.