Earlier quoted context omitted.
> The DOM is very ill-suited for most UI. Too complex and lots of missing features Can you expand on this, because I'm not seeing it myself. The DOM, html+css is very flexible. It easily encompasses most UI. Most UI is some kind of data display, so lists, trees, tables, forms. The need for JS might be what you're complaining about. I think we might be stuck with it as a UI control language forever.
The DOM(and CSS) is primarily built for documents and forms, even with the latest addition like Flexbox or Grid layouts. It is closer to typesetting tools like troff, latex, texinfo than any UI engines you can think of. And some that are not needed, like the difference between , , , ,... Also with most GUI frameworks, there's some difference between widgets like label, button, menu, checkbox,... and containers that d…
Inside HTML 5 you can find facilities for rendering documents and you can find facilities for rendering applications, including those forms. There is not a clear line between one and the other.