This reminds me of MILO for booting Linux on some (?) DEC Alpha systems back in the 90s. I don't remember much about the actual firmware anymore. Much like tod

This reminds me of MILO for booting Linux on some (?) DEC Alpha systems back in the 90s. I don't remember much about the actual firmware anymore. Much like today with UEFI, the system had some low-level UI and built-in drivers to support diagnostics, disk and network booting, etc. MILO could be installed as a boot entry in the firmware-level boot menu. MILO was a sort of stripped down Linux kernel that used its drivers to find and load the real kernel, ending with a kexec to hand over the system. No matter how you slice it, I think you'll always come around to wanting this sort of intermediate bootloader that has a different software maintenance lifecycle from the actual kernel. It is a fine idea to reuse the same codebase and get all the breadth of drivers and capabilities, but you want the bootloader to have a very "stability" focused release cycle so it is highly repeatable. And, I think you want a data-driven, menu/config layer to make it easy to add new kernels and allow rollback to prior kernels at runtime. I hope we don't see people eventually trying to push Android-style UX onto regular Linux computers, i.e. where the bootloader is mostly hidden and the kernel treated as if it is firmware, with at most some A/B boot selection option.