I'm not sure, I think the idea of scoping HTML/CSS/JS at the same level is good for development. At least when you think in terms of "components", it's easy to

I'm not sure, I think the idea of scoping HTML/CSS/JS at the same level is good for development. At least when you think in terms of "components", it's easy to see why you would want content, styling and behaviour together. Keeping things local makes everything easier in my experience. HTML also has that weird position where you have things like <video> or forms, which are not really content but entire components, but still lacks lots of things people expect from a component library.