[Swordmaker]

The new requirements went in a month ago even for people on the older OS, retroactively.

No, it has not been implemented. The public backlash was far too overwhelming.

[ConservativeMind]

Before Apple announced the feature's implementation, iOS 14.3 was released in December 2020 with an early version of the algorithm, which was tolerant to image resizing, compression and watermarks, but not cropping and rotation.[3][4]

https://www.macobserver.com/analysis/apple-scans-uploaded-content/

“.....Apple provides you with an end-to-end encryption key that ensures that messages sent to and from your devices cannot be read by anyone but you and your counterparties. But it then stores a copy of that key in your iCloud Backup, and that iCloud Backup is not end-to-end encrypted, meaning Apple can access the backup, retrieve the key and then access all those “Messages in iCloud.”

https://www.forbes.com/sites/zakdoffman/2021/09/18/apple-iphone-13-iphone-12-ios-15-users-stop-secret-access-to-your-imessages/