Lots of FUD here but the short answer is a combination of: * Hardware does degrade a bit over time * New OS versions add more features that eat up CPU cycles,

Lots of FUD here but the short answer is a combination of: * Hardware does degrade a bit over time * New OS versions add more features that eat up CPU cycles, but also add more abstractions to make developer’s lives easier but potentially be less performant. These features and abstractions are often also optimized for latest phones, since software and hardware design are so tightly integrated. * Developers tend to optimize for newer hardware, since that’s the hardware they tend to have available * Finally, there’s just been a huge amount of progress in iPhone hardware from the X to the 13.