I don't understand the benefit either right now - maybe in 5 years time or something but certainly wouldn't deliver the performance needed and the changes to software would be huge.
Don't forget that the mac was no way as popular as it is now when it transitioned over from powerpc to intel and had less apps [from what I can recall].
There is a difference between switching from niche to industry standard as they did back then and going from Intel to their own proprietary version of ARM, that would be the exact opposite.
Remember that back in the days Intel would have 5 times better efficiency while being more than twice as powerful.
Apple's ARM does have like 2 or 3 times better efficiency on low power chips (there are no high power chips for comparison) but significantly less computing power.
Before people start praising the desktop like performance of Apple's chips and talk about crushing the Core M (which it actually does not, but keep in mind - that's the
lowest core series chip, the entry model in performance regards) we should look at some things:
- Benchmarks. The main source of those statements is Geekbench. Geekbench is a benchmark which is throwing over their own charts with every "even more realistic" version of their benchmark. Some chips end up 30% ahead of other chips that were 40% ahead of them on the last "soooo realistic" version. Geekbench on ARM vs ARM is still somewhat reasonable, but on ARM vs x86? They are literally doing different things on both platforms like doubling or even quadrupling precision of Int/FPU operations for x86.
- Scalability. Main reason for ARMs better power consumption is reduced frontend. If you are saving 3W of frontend in a 5W chipset, that's huge. If you are saving 3W of frontend in a 30W notebook CPU or a 60W desktop CPU or even a 140W enthusiast or server CPU, it does not matter.
- Missing the obvious. Graphics on Apple's chips are huge, sure, but maybe we should remember one thing. They are driving 727,040, 1,000,500 or 2,073,600 pixels. 15" retina is drving 5,184,000.
- Ignoring the OS. iOS and Android compared to MacOS and Windows are absolutely lightweight.