The only reason that line has become the focal point of the essay's tone is because we're discussing this on "Mr. Graham's" site.
I didn't say it was the focal point, but it is indeed quite central to the thesis defended.
There are comments to this effect in the blog's site too, and the author felt the need for the footnote. Thus, it's not just HN bias.
The point of footnotes is that their content is not worth interrupting the flow of the main text. It should be safe for the reader to leave them for later, or skip them altogether.