I did upgrade my iPhone 12 mini to 15.7.2 recently, only to find a serious annoyance. I have iMazing set up to automatically backup my phone over wifi each day. It was very convenient and totally automatic. With 15.7.2, this can no longer happen. I have to enter the phone’s PIN every time iMazing tries to do a backup. It will not even use Face ID - it has to be the PIN. iMazing tech support says this is a change Apple made with no way around having to enter the PIN.
I have been holding off upgrading my iPad for this reason.