From: Chris Irwin via Talk <talk@lists.gtalug.org>
Latest and greatest really isn't a big deal. You can get the latest and greatest on an x86 PC without too much fuss, because there's an established standard of interoperability.
A new x86 motherboard will support UEFI, your OS boots via UEFI, therefore your OS will boot on the new motherboard. You don't need to wait for some anonymous smart person to buy the same motherboard you have and port Linux to it. You don't need to hound your motherboard manufacturer to release Linux modifications under the GPL.
Note: I'm not talking about specific hardware drivers (ex: GPU, fingerprint reader, etc). Merely the ability to boot an OS itself.
That's not the case with most ARM platforms, especially in phones. The on-device firmware is extremely minimal, and the OS itself is expected to know the inner workings and intricate details of the hardware.
That's why you have "Raspberry Pi OS" instead of just shipping plain-old Debian. That's why the Pixel 3a has support in Postmarket OS, but other devices with similar hardware don't.
This could be solved. Requiring UEFI on ARM, for example. Microsoft required it for Windows on ARM devices, as they don't want to support device-specific editions of Windows (now, those were locked down via restricted secure boot, but that's *yet another* topic).
Instead of a manufacturer modifying Linux with hardware details, they'd instead do those modifications in UEFI. Yes, we'd still need device-specific drivers (for ex: GPU, etc), but lets just deal with the ability to *boot* an OS first.
The UEFI implementation doesn't even need to be burned into the firmware. PFTF [1] built UEFI for the Pi3 and Pi4. It works very well abstracting the Pi-specific details, allowing *Generic* ARM Linux to boot (no need for a Pi-specific build).
The Snapdragon X notebooks are ARM, UEFI, and are supported poorly by Linux. Too many features are undocumented. Interestingly, different brands are supported differently. There was a claim that Linux support would be forthcoming, but it looks like the notebooks will be obsolete before there is good support. <https://discourse.ubuntu.com/t/ubuntu-concept-snapdragon-x-elite/48800> These computers have seen recent large discounts. I take that as some kind of indicator of failure. But it just might be because the new line has been revealed. (When I saw these deals I got interested but then discovered how poor Linux support was.)