In iOS 16, are photos & videos in the hidden folder secure in iCloud, so hackers would not be able to access?

In iOS 16, how secure are the photos & videos in the hidden photos album. Are they accessible only with a password in iCloud, so hackers would not be able to see & threaten/blackmail to post them somewhere?

If this is not the case, is there someone from Apple who reads this, & include the feature in a future iOS update?