One nice thing about getting feedback is learning all of the additional stuff I should have included in the blog post. I did look at number of articles per year, and it fluctuates, but there isn't a huge change across the century, and the change goes up and down. Total words, on the other hand, does trend up and goes up faster more recently.
You'd probably see the same effect if the articles don't get any longer, but more of them get written every year. Unique word count will always go up with words produced, even if most words produced are formulaic boilerplate.