I think labelling it as a bootloader control issue is mislabelling it. It's a question of what operating systems can be loaded, which is a subtle distinction.

In any case, I think the Byte article gets a good angle on the antitrust case. I also think that the issue of browser integration (while interesting and worthy of contemplation) was hugely overplayed; the more egregious monopoly abuses were completely downplayed or overlooked.