- Battery Management (iPhone 6, 6s, and SE): In 2017, Apple introduced a battery management feature in iOS 10.2.1 to prevent unexpected shutdowns by throttling the performance of iPhones with degraded batteries. This led to slower device performance without informing users, which is a removal of expected performance functionality.

- 32-bit App Support: With the release of iOS 11 in 2017, Apple dropped support for 32-bit apps. This meant users could no longer use older apps that had not been updated to 64-bit, effectively removing access to those apps on updated devices = You want the new OS? -> you have less functionality.

- Pulse oximetry features were recently removed from new Apple Watches due to Masimo's patent infringement claim.