That is not true. iCloud Backups are encrypted using the device's PIN. The only data that Apple would be able to provide is SMS data because that is not encrypted when it's sent and it's not encrypted when it's backed up.
AFAIK iCloud backups are not end-to-end encrypted. I believe this past February Tim Cook, or someone else at Apple, was indicating that they were working on changing that. (It was coming up because everyone was wishing the San Bernardino shooter's phone had been backing up to iCloud, so they wouldn't need to get in the phone, they could just access the iCloud backups—IIRC.)
https://www.apple.com/legal/privacy/law-enforcement-guidelin...