The Broadcom SoC used in the Raspberry Pi hasn't aged terribly well, there is a pretty good thread comparing the various boards out there on the Armbian Forum[1], in it they discuss how much power boards use with different parts enabled. Some Allwinner boards (like the PC2) can use just 1w at idle without disabling anything. Further savings is possible if you disable gigabit ethernet, GPU, etc. More info is in the 2nd link!

1 - https://forum.armbian.com/topic/1748-sbc-consumptionperforma... 2 - https://docs.armbian.com/Hardware_Allwinner-H3/

Oh sure. It was more a point about software polish. All these SoC's have hardware support for clock gating and separable power domains and deep idle states, etc...

But in general, making all junk work is a huge rats' nest of complexity. And in practice, except for a tiny handful of devices from top-tier manufacturers, it just doesn't. Maybe it works "most" of the time. Maybe there are tuning tricks you can use that get the power down but break two or three devices in crazy ways.

But Apple has the smarts and resources to ship a power-hungry part and guarantee that it sits at a clean idle reliably. And Qualcomm isn't far behind as long as they have an integrator like Google or Samsung breathing down their neck. But all the other junk? Yeah, junk.

All parties that run Linux on these devices should be forced to mainline their kernel patches. The patchwork of shitty BSPs that both Google and Samsung have created were shipped, resulting in hundreds of millions of insecure, poorly supported devices that are actively used.

Look at what Armbian has done with these bespoke chips in spite of limited resources, had Google and Samsung put in a minor amount of effort, akin to what Sony has done, the Android landscape would have many more users running fully patched, slightly less buggy software today.