I call it a bug; someone else on this board called it a data-loss bug; Apple probably calls it improved design.
Configured Mac to automatically sync when the phone when connected.
Plugging into mac with lightning cable, iPhone and iPad pop up a screen asking for passcode to trust computer and start a backup.
Once is fine, but it doesn't remember that I trust this computer. Next time I plug it in, the phone again asks for permission.
This breaks the old well-established behavior of setting it up once and it automatically backing up when plugged in, without user interaction.
I submitted a new feedback on this one. iOS/iPadOS 16.1 (20B82)