I don't fully agree with your second point. The way iCloud on an iPhone works, users have no chance to encrypt data before uploading it. Most people are only tangentially aware of what data is siphoned automatically by the service.
It would be the responsibility of the iCloud service to encrypt data (if Apple had chosen to do so, and a user opts in). Simply choosing not to delete encrypted blobs is not the same thing. The salient point is that Apple was _going_ to offer encryption as a part of the iCloud service, but dropped the feature at the FBI's request.
They are required by law to do the latter. They are not required to to do the former (or at least are willing to go to court to defend that belief).
> They also don't allow users to encrypt data stored in iCloud
The article you linked does not back up this assertion. It says they chose not to automatically encrypt user backups to the cloud, at the FBI's request. I'm sure if you encrypt data and upload it to iCloud, they will not delete your encrypted data.