I registered just to reply to this.. iPhone 7 bought in 2018. Since 2018 original battery has expired and last miserable half a day, I replaced the battery myself (I'm a cell phone repair servicemen in Russia) - I used VIXION brand battery. This was in mid February 2021. First 3 weeks battery life was magical, it would take me about 5 days of normal use to get the battery down to 20%. But then I picked up an iOS update and then another one. Presently iOS version is 14.4.2, so since I updated 2 times, that means iOS version when I changed battery was minus 2 versions. Right now, I did this as experiment, if I charge 100% and disconnect charging cable at midnight and put the phone into silent and airplane mode, at 8 am the phone is 70% charged. I knew the battery is good and can not go bad this quick. I thought something is up with the phone, perhaps planned obsolescence by Apple. So I go online and find this post. You know what I think this is? This kind of battery usage for any prolonged amount of time would kill the battery on any phone. I believe this update was done on purpose so that batteries go bad. Batteries go bad people make money. Apple make money. I make money. By the way, this is the last iPhone I'll be using. I don't even buy these phone, I get them for free, still no thank you. iPhone is not reliable.