And that's sort of the point, in my mind: the page is about a megabyte, while something comparable on the modern sites he's talking about would be many times larger. As you say, it's a megabyte because there's a megabyte of content, not a megabyte of Javascript and trackers and "From Around The Web"

Back when I was on 28.8K dialup, I'd typically figure I could fetch a megabyte a minute. Because the site is just plain old HTML, even over a terrible connection you'll be able to start reading pretty much immediately, and the images will pop in as you go. It's a good user experience.