Again: how often do Fedora users boot their systems? I think l10n of the boot process is pretty pointless compared to being able to see the GRUB screen and actually solve the problems when they occur. Untranslated messages during the clean boot process can be ignored, but not seeing the _error_ messages (even untranslated) and the GRUB menu at all is much worse.
In my opinion the "Outright bugs" section in the original article contains a single outright bug, which is #9 about the boot loader spec. All the others are minnor usability/polish problems, or even enhancement requetsts (#5 about brltty). And in my opinion it is not wise to trade enhancements (for some users) or even polish for something that is outright regression for other users.