Double-tap on the text. Like the article says. It really does work, quite often way better than attempts at responsive design. And then there's the reader functionality in my phone.
The issue isn't, I think, responsive design itself, it's that it's not so trivial to make it work better than device-based workarounds.
Is it just me, or is double-tapping on text still not usable enough? Every time I do that, my finger inadvertently slides horizontally instead of vertically, and I need to re-center the text to continue reading.
This is one of the main reasons I love readers like Instapaper.
But why require someone to double tap on the text? On a blog like this, the primary action of the user is to read the article. It's bad user experience to require an extra unnecessary step to do the primary action.
Because you might have some more pressing issues to fix than that -- it's not a good experience, but, unless you did something horrible (which newspapers often do, unfortunately), it's not that bad either. It is economy of time and attention, especially as there's always a risk that your "better" version won't be good enough anyway, and people like me will use the text extraction features of the browser anyway.
Edit: I don't mean to say that it's necessarily a bad idea to go responsive -- it's just that it's not a clear, universal win.
The issue isn't, I think, responsive design itself, it's that it's not so trivial to make it work better than device-based workarounds.