No, that's the whole point of the article! Pure black text on a pure white blackground is too much contrast, which is uncomfortable for the eye over a long period of time. It's bad for readability.

Use dark gray on white, or black on light gray, but don't use pure black on pure white. It's too much.

Remember, the contrast between white and black on computer monitors is greater than on the printed page, because computer-monitor white is brighter than a page usually.

The printed page only achieves this level of high-contrast when you're in broad daylight, like on the beach. And of course, most people wear sunglasses in that case, because it's too much.

(Of course, there are exceptions to every graphic design "rule", but avoiding pure black text on a pure white background is pretty standard one for webpages.)