Remember, the leader of the pack on this issue is RMS. He's not looking for a world of coexistence with Microsoft -- he wants them to go away and not come back. If you try to get inside of how he'd be approaching this issue you get to, "What about when Microsoft is on the way down? Will they fire back with these things?"

However, RMS is also pretty true to his stated purposes there; he'll welcome things back to the fold when situations change (e.g. the Qt / KDE schism over Qt's licensing), but he's not one to look at things from a good faith perspective when there's no guarantee of followthrough.