In addition, from Apple--iMessage Contact Key Verification, Security Keys for Apple ID, and Advanced Data Protection for iCloud provide users with important new tools to protect their most sensitive data and communications: https://www.apple.com/newsroom/2022...-security-with-powerful-new-data-protections/
As I understand it, the backups are encrypted in transit and at rest but Apple has access to the keys. There are other cloud things and services (14) which are currently end-to-end encrypted--user owned keys. Apple is claiming they'll expand (user opt in) end-to-end to nine more categories , which will include backups. We shall see. The current and future encryption status according to Apple: https://support.apple.com/en-us/HT202303
