@neal As a former PowerPC user on OpenSUSE. It was an interesting beast. I will iterate that Yaboot was the easiest experience on OpenSUSE when it would inevitably break, all down to YAST and not needing to figure the incantations that differed from distro to distro on fixing unsual issues that would pop up. RIP Yast ._. i will miss not being able to do the things it did while SSH'd or via a serial console to fix things.
Still OpenFirmware was pretty neat so i agree.
@neal When UEFI was implemented initialy it was still 32bit as well while Openfirmware was 64 and if i recall there was a working 128bit build. We would not have had the oddness that was the first couple versions of intel Mac with their 32bit EFI implementations on hardware that was 64bit or 64bit upgradeable. Remember when Macs where upgradeable?
One issue i see is how would Microsoft have forced their propritary implementation of secureboot and other boot stuff into it?