[josteink]

Fastboot is a interface/protocol to talk to the bootloader, in order to flash images to select partitions. On select phones. And it requires an external device to run the process. So it can't be self-hosted.

All that technical whizbang doesn't change or even address the underlying problem: What you boot still needs to be 100% device specific.

There's no UEFI/BIOS on ARM to help bootstrap the boot process.

Also: When you flash custom roms on Android, you format and then unzip a file onto the system partition. Not that I see how that's technically any different from flashing a FS-image, but if it matters to you, now you know.

In conclusion: none of my claims have been near disproven, but a few straw men has been presented to be stricken down ;)