I have gradually reduced CSS to zero myself, since pretty much every tweak seems to mess up accessibility more than improve things, and generally it is the client that should control the style, and the user who should configure it for themselves, knowing their own requirements better. As for suggestions from the article:

> Granted, if you have images they can cause some overflow issues.

The "fix" breaks zooming in.

> In general, the font-size is a little small as well

It is quite annoying when websites mess with your preferred font, its size, style, and so on, often turning texts illegible. In this case it is made awkwardly large, but often it is made illegibly small, apparently also with the intention to fix the defaults.

> Many people love dark mode, so let’s enable it based on a user’s system preferences.

"color-scheme" is like "viewport": an invocation to tell the browser that the website is not too broken, and the web browser should act more sensibly. Those are practical, but still awkward, not quite how things should be: I wish web browsers defaulted to sensible behaviors. So I rather view it as a choice between adapting to how things are and pushing for how they should be.

> We generally want to try and fall somewhere in the 45-90 characters per line range (for body text, not headlines).

I used to set max-width in ch before removing CSS completely as well, but usually desktop web browser windows are resizable, with the space being there to be used, not to fill with background color. I see it in epub files sometimes as well: huge margins are enforced, being rather annoying when you do not want those, while if you do, you can simply adjust the window size (or set such default styles, as another option).