Alongside iOS 26.2.1, Apple today released an updated version of iOS 12 for devices that are still running that operating system update, eight years after the software was first released. iOS 12.5.8 is available for the iPhone 5s and the iPhone 6, meaning Apple is continuing to support these devices for 13 and 12 years after launch, respectively. The iPhone 5s came out in September 2013, while the iPhone 6 launched in September 2014.
They’ve generally always supported their phones significantly longer than anything on the other side.
Security updates such as this for devices able to acces services makes sense.