Part of the ‘loyalty’ to Courier and its variations might be sheer pragmatism – generally speaking, it’s what the publishers want. It can be a jarring moment when a manuscript created in Times New Roman gets converted to Courier and it’s suddenly 150 pages longer… Even more jarring when you get THAT call from your editor. In the long run, it’s easiest to start off how you’re going to end up. That way everybody’s on the same page (literally AND metaphorically) from the outset.

>>Why not try some Big Caslon once in awhile, with a sprinkling of Zapf Dingbats

I read the article, and it looks like the answer is in the rest of the quote from Andrew Vachss (spelling, man!): “Fancy fonts are fine for blogs, just as calligraphy is fine for diaries. But when you’re writing for anyone other than yourself, you want to get as universal as possible.” Since all of the people quoted are published writers, they are aiming for what makes their readers’ lives easy.

Actually, I think the main reason people have an affection/nostalgia for Courier comes from its intended resemblance to typewritten text. Also, Courier was commonly used for old dot-matrix printers, and it’s also the standard font in some text-editing software. People got used to its monospaced weirdness, kind of like the persistent preference for vacuum tube audio or vinyl LPs.