If your iPhone battery is showing signs of degrading, you might be better served by spending $60 on a new iPhone battery and changing your battery management practices. Joe, Joe, Joe, my first sentence started with "I got a new battery for my phone"! LOL!
Oops! When I get on a roll, I sometimes forget where I started or where I was going.
By-the-way, because of my penchant for running beta releases, my experience may not be typical, but I never encountered any battery issues in iOS 15 other than some initial extra drain early on. I have never had reason to pay close attention to battery usage, but by iOS 15.6 beta 5 I would have sworn battery consumption was noticeably reduced. I am now running iOS 16 so I can no longer verify any of that.
