Really? They do this just to work at cross-purposes to their other teams which spend time and money to maintain software updates for older phones, 4-5 years longer than competitors do? How do you explain that one?
Why not? It is a big company, with different teams having somewhat different priorities. It is perfectly reasonable for the upper management to leave the tech department supporting the devices for a long time, and thus maintain and increase the brand value, while keep the anti-consumer anti-environment business policies regarding repair. They can brag about how the Apple devices are great and long lived, and sell lots of new units/repairs every cycle. It makes perfect sense.