It's probably paranoia, but I feel like my 5S battery is draining faster since the update.
That being said, the performance upgrade is well worth it.
That being said, the performance upgrade is well worth it.
I assume the iOS12 update includes a combination of more aggressive waking and maximizing of performance along with a reverting of what they did previously to old phones when they lowered their performance to maintain the battery life of the degraded battery. If you remember there was quite a bit of scandal about this earlier this year.
My guess is your old iPhone's battery will also last half as much as it did originally within months. Yes, it's a factor of the new changes, but let's not forget it's primarily a factor of Apple using batteries that lose a significant percentage of their capacity after 2 years in the iPhones, and then hiding much of that by slowing your iPhone down. Maybe Apple should put higher quality batteries in their phones - just saying.
Compared to what available and suitable miraculous technology?
As far as I can tell this simply isn't true. My iPhone SE is at 89% of maximum capacity after 2.5 years of very regular use. It's standing up pretty well.
I think it was mostly immature technology adopted relatively early. There have been advances in battery tech, and it takes time to work kinks out.