I assume this is referring to the tweet from the launch of the M1 showing off that retaining and releasing an NSObject is like 3x faster. That's more of a general case of the ARM ISA being a better fit for modern software than x86, not some specific optimization for Apple's software.

x86 was designed long before desktops had multi-core processors and out-of-order execution, so for backwards compatibility reasons the architecture severely restricts how the processor is allowed to reorder memory operations. ARM was designed later, and requires software to explicitly request synchronization of memory operations where it's needed, which is much more performant and a closer match for the expectations of modern software, particularly post-C/C++11 (which have a weak memory model at the language level).

Reference counting operations are simple atomic increments and decrements, and when your software uses these operations heavily (like Apple's does), it can benefit significantly from running on hardware with a weak memory model.

  It seems if you want optimal performance and power efficiency, you need to own both hardware and software.

Here's an M4 Max running macOS running Parallels running Windows when compared to the fastest AMD laptop chip: https://browser.geekbench.com/v6/cpu/compare/13494385?baseli...

M4 Max is still faster even with 14 out of 16 possible cores being used. You can't chalk that up to optimizations anymore because Windows has no Apple Silicon optimizations.

Intel is busy fixing up their shit after what happened with their 13 & 14th gen CPU. Making imagine they making OS its called IntelOS and the only thing you can run is only by using Intel CPU

Or, contribute efficiency updates to popular open projects like firefox, chromium, etc...

Wouldn't it be easier for Intel to heavily modify the linus kernel instead of writing their own stack?

They could even go as far as writing the sleep utilities for laptops, or even their own window manager to take advantage of the specific mods in the ISA?