A logic issue was addressed with improved file handling. This issue is fixed in macOS Ventura 13.7.2, iOS 18.2 and iPadOS 18.2, iPadOS 17.7.3, macOS Sonoma 14.7.2, macOS Sequoia 15.2. Photos in the Hidden Photos Album may be viewed without authentication.
https://support.apple.com/en-us/121842
https://support.apple.com/en-us/121840
https://support.apple.com/en-us/121839