i don't think vanilla html saves more bandwidth than JavaScript. if a part of your website needs update (react,vue,fetch) only that part is transmitted over the wire. It's also less jarring for the user, since most browsers would scroll the content to the top. Also, without JavaScript, some webapps would require storing user state in a server database rather than in memory of the browser. Fix html and we won't need J…
Jarring for the user? Are your users cavemen with severe PTSD? Loading a web page is not a "jarring" experience for anyone. Was the first load of your page "jarring"? Was loading a new page "jarring"?
This idea that users are hyper delicate flowers is ludicrous. Having a page stuck with a bunch of gray gradient placeholder elements while JavaScript loads and does whatever is far more jarring than a page that just loads.
Edit: autocorrect can get bent