This is just security theater, they already sign the operating system images where the database reside. And there is no way to audit that the database is what they claim it is, doesn't contain multiple databases that can be activated under certain conditions, etc.
> This feature runs exclusively as part of the cloud storage pipeline for images being up- loaded to iCloud Photos and cannot act on any other image content on the device
Until a 1-line code change happens that hooks it into UIImage.