Since you're asking: on Firefox/Android the page rendered in the declared three column layout. Even after I manually zoomed in to make the center column fill the width of my screen, the text was very small.
Usually, I'd just use Firefox Reader View (aka Readability.js), but it's not being offered on the site. I don't know why, the document structure seems straightforward enough (IANA web dev).
Oooh, I tried that, it does not make the experience better (at least in Fennec on my Android): the main column gets squeezed until it only shows one word at a time. I think I'd have to drag my websites CSS into the 21th century before I can use that.
Ah, that's too bad. You can use two CSS selectors to make the two columns go under then main one on small screens, though it's a bit more involved than I can remember off the top of my head.
Usually, I'd just use Firefox Reader View (aka Readability.js), but it's not being offered on the site. I don't know why, the document structure seems straightforward enough (IANA web dev).