alt Hacker NewsAh...you're scratching at some scabs with this totally reasonable question.
We learned some tough lessons with media-chrome[1] and Mux Player, where we tried to just write web components. The React side of things was a bit of a thorn, so we created React shims that provided a more idiomatic React experience and rendered the web components...which was mostly fine, but created a new set of issues. The reason we chose web components was to not have to write framework-specific code, and then we found ourselves doing both anyway.
With VJS 10 I think we've landed on a pretty reasonable middle ground. The core library is "headless," and then the rendering layer sits on top of it. Benefit is true React components and nice web components.