I definitely remember it being pitched as the future of Windows UIs, while having massive feature gaps, and, perhaps most noticeably, looked blurry and horrible

I definitely remember it being pitched as the future of Windows UIs, while having massive feature gaps, and, perhaps most noticeably, looked blurry and horrible on the standard displays of the era (ie, non HiDPI). Why the engineers thought that it would be a good idea to build a resolution-independent UI with no pixel hinting targeting 96ppi displays is utterly baffling. Silverlight made perhaps a bit more sense since it was almost entirely graphics-focused, but it never really stood a chance against the massive install base that Flash had back then.