Is it not a web component, per se? Per the article, all the React stuff does seem to bake down to HTML Custom Elements, that get wired up by some client-side JS registering for them. That client-side JS is still a "web component", even if it's embedded inside React SPA code bundle, no?

If you mean "why do I need React / any kind of bundling; why can't I just include the minified video.js library as a script tag / ES6 module import?" — I'm guessing you can, but nobody should really want to, since half the point here is that the player JS that registers to back the custom elements, is now way smaller, because it's getting tree-shaken down to just the JS required to back the particular combination of custom elements that you happen to use on your site. And doing that requires that, at "compile time", the tree-shaking logic can understand the references from your views into the components of the player library. That's currently possible when your view is React components, but not yet possible (AFAIK) when your view is ordinary HTML containing HTML Custom Elements.

I guess you could say, if you want to think of it this way, that your buildscript / asset pipeline here ends up acting as a web-component factory to generate the final custom-tailored web-component for your website?