I’m sorry if this sounds like a stupid question but why won’t android just straight up run like Linux distros that almost run on any computer? Why does each model under each manufacturers require separate maintainors seperately? Aren’t they running like almost similar hardware like processors from Qualcomm, mediatek, Exynos, etc? Why hasn’t there been a single android os that is compatible with all the device?
There are 2-3 major roadblocks. Like others mentioned we simply lack drivers. But in my opinion the biggest issue is the lack of a BIOS equivalent for ARM systems.
Most PCs use x86 processors while most phones use ARM processors. And most x86 systems come with a BIOS (nowadays UEFI). That is a very simple operating system that runs when the computer starts and it gives a standard way for other operating systems like Windows and Linux to start up. That way the same x86 operating system can start on just about every x86 computer.
ARM lacks this standardisation. Although there do exist some projects to fix this they are not in use on most phones. So you actually have to make a custom way to just start up for each and every phone.
On top of that and the general lack of drivers many manufacturers lock their phones down so that only their own operating system may start.