Then why is battery life terrible on iOS 26 and the device is heating up just doing basic stuff with the UI. And it stutters a lot too in places even with a 16 Pro.
It would be an interesting napkin problem to do. Yes it's relatively trivial, but multiply it by 1B smartphones running for many hours every day and how many cities worth of power are you wasting on extraneous shader cycles?
It’s still very little energy. Probably way way less than a bedside lamp per phone.
Phones aren’t a good place to try to save aggregate energy use at a population level. They already use vanishingly small amounts of energy compared to just about anything in your house.
The GPU compute used by this is trivial for modern SoCs.
There is so much power and efficiency in a modern iPhone processor that these simple shaders are entirely negligible.