Funny how these things go in circles. I remember the time where many webpages were unstyled, letting you freely choose the font, size, colors, etc. in browser preferences. But that was considered ugly and non-user friendly. Now with various readability buttons we're just moving back to that.

Without custom CSS, you couldn't, however, fix the single most important readability issue about unstyled HTML: add reasonable margins and keep body width at the recommended 60–70em or so. Readability modes finally get that right.

Right. I forgot to mention that we also used to be able to resize the browser to the width we personally found comfortable for reading. I guess that's something reader modes still have to rediscover.

Sure. But lines running from window border to window border are still hard to read. The margins have to be clean negative space.

Every single time I see a medium link, I prime my cursor to hit Reader Mode as fast as possible, it's a godsend.

See https://news.ycombinator.com/item?id=19035256

You can open links directly in reader view with the Open In Reader View addon for Firefox/Chrome/Opera:

https://add0n.com/reader-view.html

It's great for these situations.

No need for an extension.

Reader view doesn't always work though (at least in Firefox.) You can use the icon in the URL bar or CTRL + ALT + R to open reader view.

Firefox does some detective work to choose whether to show the reader view icon but using the keyboard shortcut used to work regardless. Recently it seems even the keyboard shortcut doesn't work unless the icon is visible - I think becausethe heuristic for showing the icon is more accurate these days.