I think the web really needs some "decluttering". The ratio of processing power by useful payload nowadays is unsustainable.

I completely agree. However, I think browsers are also to blame in some part.

On web sites that I build, I sometimes get alerts from Safari that my page is bogging down the computer and it offers to "reduce protections" to make the page perform better. But this is always on pages that are plain HTML and CSS, and don't even have animations. No Javascript. No canvas. Not even forms. And the total payload is often less than 20K.

I don't know what else I can do to make it lighter.