I created an account just to comment on this. I upgraded from an iPhone Xr to a 256Gb iPhone 14P. The battery life on the Xr was amazing when I first got it, but it's a little less now, battery is around 80%, easily gets through a full day. Moving to the iPhone 14 Pro has been an awful experience. The battery life is terrible, like android from 2013-2014 bad (nexus 5). this is the 6th day I've had it now and it doesn't appear to be getting better.
I wiped it on Sunday to see if it would make a difference, everyone was saying it would fix it, but it doesn't appear to have done anything. Here is an example for today. I started to charge it last night around 1:30am with 55% charge and it was only at 97% at 7:30am with a 5 watt charger (that's whats next to my bed). Anyways its 1Pm now, I have 2 1/2 hours of screen time and its at 38%, mostly emails, some reddit, and some phone calls. I doubt this phone can make it to 5PM with its current charge. I thought I was going to get more screen time with this device, but it appears to be way less.
I've attached two photos, the first is when I left it unplugged one night after a 80~% charge, the second night I owned it. I think the battery dropped by 40-50% by the morning... that's ridiculous. The second is just the 2 /12 hours of use today.