Javascript is not required to read it. Javascript is used to provide extra functionality outside of the download / render cycle, to speed the experience of the page up, and to make future navigation faster.
I understand where you are coming from, but you picked a bad example.
That is one thing I'm totally not buying. How does JavaScript speed anything up over simple staticly rendered text, (which is what Medium should be)?
In an ideal case you could have a fast initial page load with static HTML. Then an async script tag quietly loads a script in the background while the user is reading (done properly, this can be imperceptible). Then when the user clicks a link, JS handles it and instantly updates the DOM and location bar, faster than would be possible with a static page load.
That's not usually the reality but it's definitely possible.
>Then when the user clicks a link, JS handles it and instantly updates the DOM and location bar, faster than would be possible with a static page load.
In the GP's example, the first page load is already rendered by the server. It's subsequent page loads that are rendered in JS.
Because if it's just to display comments or something, I stand by my original statement.
* 10 XHR requests on page load
* 3 downloaded fonts
* Continuous XHR requests as you scroll through the article
* ~400ms time spent executing javascript (according to timeline benchmark)
I'm not really sure why all those things need to happen to load some text in a blog article.