No idea what you mean by "well built OS" when Android has so many corner cases and weird "hard coded work arounds" and crazy development process that its behavior is often unpredictable and downright irrational.
And what do you think iOS / macOS is based on? UNIX userland from the BSDs with the Mach kernel, Mach IPC, etc. Fun note: It's easier to cross-compile standard UNIX utilities and programs for iOS/macOS than it is Android since Android effectively has its own user-land.
macOS and by extention iOS are, by comprarison to Android, actually pretty well architected. The choice of kernel (Mach, Linux) is really not the limiting factor, it's how you plumb together the layers above the kernel and that's what Android has done badly.
Lastly, just because OpenMoko may or may not have done something ideally (~20 years ago?) doesn't mean the current efforts (postmarketOS, Plasma, PHOSH, Sailfish) have done it badly. Actually most of these efforts are leveraging the fairly refined parts of a modern Linux environment and are MUCH easier to work with at the lower levels than Android.
And what do you think iOS / macOS is based on? UNIX userland from the BSDs with the Mach kernel, Mach IPC, etc. Fun note: It's easier to cross-compile standard UNIX utilities and programs for iOS/macOS than it is Android since Android effectively has its own user-land.
macOS and by extention iOS are, by comprarison to Android, actually pretty well architected. The choice of kernel (Mach, Linux) is really not the limiting factor, it's how you plumb together the layers above the kernel and that's what Android has done badly.
Lastly, just because OpenMoko may or may not have done something ideally (~20 years ago?) doesn't mean the current efforts (postmarketOS, Plasma, PHOSH, Sailfish) have done it badly. Actually most of these efforts are leveraging the fairly refined parts of a modern Linux environment and are MUCH easier to work with at the lower levels than Android.