I can confirm having the same issues on both iPad and iPhone 12 running latest iOS14. With COVID I hadn’t been outside a lot and only noticed that my devices drained battery quite a lot with just sitting there. I often ran out of battery in the evening without heavy usage. However when traveling all the sudden I still had 60%+ at the end of a day actually using the phone. Other family members do not have the problem on the same network connected to the same family shared home. Home consists of 2 Apple TV’s, homepods and probably 20 HomeKit devices. All works well. it is very concerning that this thread is this old and the problem has not been resolved yet.