I wonder what change in the linux kernel caused the increased load. Someone out there is responsible for this crime!
How long has there been a power consumption focus in the linux kernel? The efforts to reduce power usage by the linux kernel pre-date PowerTOP’s first release and wiki tells me that was 2006.
Is Apple way ahead or is it just less popular?
They're definitely solving a narrower problem but they do appear to have it solved. Is there even a subset of hardware configurations for which this is the case with Linux? (if there is I would love to know about it)
That's not how cross-platform, cross-application software works. Linux is used for everything. Every other change for power efficiency will get balanced out by another change for raw performance.
The amount of testing that Linux goes through is staggering.
This has to be a specific bug on that platform in its specific configuration.
https://en.wikipedia.org/wiki/Continuous_integration
... basically check every small commit, ideally end-to-end.
On Android, the scheduler can have a decent impact battery life