The goal of what folks call "universal web components" isn't (or shouldn't be) to create a single universal UI library -- that would indeed be a pipe dream. I

The goal of what folks call "universal web components" isn't (or shouldn't be) to create a single universal UI library -- that would indeed be a pipe dream. Instead, the goal is (or ought to be) to create a native, app-directed API for creating and manipulating UI components. HTML and the DOM are a universal content format and API, and we need its equivalent for web apps (as opposed to content). The web is a strange dualism between content and apps[1], and unfortunately, the app side has been forced to implement its constructs on top of an API that at its most fundamental level is built for presenting content. [1] I like the diagram on page 33 of Jesse James Garret's seminal The Elements of User Experience: http://www.jjg.net/elements/pdf/elements_ch02.pdf http://www.jjg.net/elements/pdf/elements_ch02.pdf