Earlier today, Apple issued a fix in iOS and iPadOS 17.5.1. Patching buggy software is a good, normal thing. But that’s not the issue here. The issue is that the fix “addresses a rare issue where photos that experienced database corruption could reappear in the Photos library even if they were deleted” — and that’s all Apple has to say about it.
On iOS, deleted photos technically spend 30 days in the Recently Deleted folder before disappearing for good, but the intent to send a photo to digital oblivion is still there. A reasonable person would expect a deleted file to stay that way. That’s why it’s understandable that people freaked out last week when photos deleted years ago had suddenly reappeared in their iPhone photo library.