The oldest iPhone, like the iPhone 6 or 6S, but also the iPhone 7, are losing power as their batteries lose capacity. This is done by software, because Apple has programmed its operating system so that, if the battery is worse, the phone will slow down and try to alleviate the problems related to it.
This seems a direct response to the many problems that the iPhone 6 and 6S had last year with their batteries. Many went out suddenly with almost half their capacity and others directly stopped working. To alleviate this, the iOS 10.2.1 update included a system to manage the power of the devices according to how good or bad their batteries are. And apparently, it is a system that has now reached the iPhone 7 with the 11.2 update.
In an official statement, Apple has ensured that its goal is “to give the best experience to users” so that their phones work and last as long as possible and recognize that the cold, the low battery charge or aging can make the dispositive.
Apple says that this will continue to be the case in future devices. And although they may be right to do this, because it would guarantee a longer life of the iPhone, users may not see it so kindly, because their phones at the end are slower and there is no way to solve this except if updates are avoided, which You can leave the device unprotected and without new features.
Similarly, it is not clear if the new operating systems are sufficiently adapted to older devices. Beyond the power difference between an iPhone 6 and an iPhone 8, if Apple does not adapt its software well to the limitations of the previous models, that can also lead to worse operation.
The debate around programmed obsolescence never seems to end, because this revives what many users fear: that the great technology companies, even those that support their devices for years (Apple is one of them) also harm the experience of their users enough so that buying again seems always the best option.