It's a language paradigm thing. You can implement anything, from HTML to CSS, in pure imperative JS, but the result would be extremely verbose and virtually imp

It's a language paradigm thing. You can implement anything, from HTML to CSS, in pure imperative JS, but the result would be extremely verbose and virtually impossible for machines to interpret on the fly (i.e. little accessibility support). There is concrete value in stating unambiguously "this is a <form>" versus "this is a blob of imperative code that I swear acts like a <form>".