Microsoft is being overly aggressive and has ulterior motives that don't align with their users. Very typical of their short-term Machiavellian style of thinking. Tactically they are making a questionable decision.

They are trying to break a very reasonable compromise that would have benefited almost everyone. Instead, as one of the largest tech companies that doesn't depend on advertising revenue, they are trying to use their power to cripple competitors. They won't win. Online advertisers are too powerful (and drive too much of the growth in the economy nowadays), legislation won't regulate the industry in a way that will hand Microsoft a victory. Meanwhile, IE's users will lose because their choice to be tracked will be ignored.