It's great to have so much innovation, but when each innovation is incompatible with the next it makes it very difficult to actually use the better things. You can't incrementally adopt them, you have to port an entire application.
This in turn makes it harder for new entrants to get adoption, even if they're better in some ways, because they need to reach a critical mass before many people are willing to put in the effort to, and accept the risk of, porting a whole app.
If we establish the base component layer and interop with the platform and other components - which Web Components does - then people can innovate on the internals of components, things like how and when DOM is updated. This is mostly what's being focused on anyway, the component models themselves are usually pretty comparable.
Not to mention that Shadow DOM is incredible and just fixes CSS.
If Firefox finishes up their Web Components implementation soon, we'll be at 3/4 major browsers with native Web Components support. I think more people will take them as a given for basing their UI libraries on.