Except that it won't be. It will be in flash. And odds are most motherboards won't even implement basic protections to disable writes after POST/BIOS because they all want to keep the cute Windows based BIOS update features. And besides, how else is a revoked key list going to get updated?
But it really doesn't matter if Ubuntu gets away with their hack of the letter of the spec. I suspect lawyers will get brought into it before it is over but if they win it will be game over. Try again with a new & improved lockdown for Windows 9.