> No, drop down menus, pre-validation of forms, adaptive rendering are the daily experience. Javascript is just the way we currently achieve that. I argue that a better html would avoid having to do this in javascript, as these are standard features that are needed everywhere.

You can certainly standardize a certain set of feature and put them in a non-turing-complete language like HTML, but standardizing all the legitimate use-cases of JavaScript is almost impossible, you talked about «drop-down menus, form validation or adaptive rendering», but what about interactive charting, modal view of full-size pictures, auto-completion of search tags ? These are just features I use on my personal blog ! And what about infinite-scrolling ? What about partial content-update ? There are thousands of legitimate use-case for JavaScript: it's not achievable to standardize every single one of them and put it in the HTML, and even if it were possible, do you imagine the nightmare it would be to learn HTML then ?