Isn't most of the text on the page grey? It's not white, it's rgb(215,215,216). And the background is not black. Some worse examples are shown, but then the message comes across as "don't use grey unless you know what you're doing, like I do, because I'm using grey while I tell you not to use grey, but mine is okay."
Maybe aside from the unset option, something more specific about a minimum contrast threshold would be useful. Ideally the author wouldn't be breaking below that threshold themselves while explaining it.
That, plus the line "Or, you could just not do it [change your colors with CSS] in the first place which would look like this:" — followed by a super-duper-CSS-styled box thingie full of gray text.
Indeed the WCAG guidelines provide the following criteria
* The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following
* Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1
Grey is not the problem. Low contrast is the problem.
WAVE shows that light mode is 0000ff on ffffff, for a contrast of 8.59:1.
For my tastes,
that's a bit too much contrast,
and I'd prefer the background be very slightly off-white, around fafafa.
The example "grey text on an off-white background." is 6D6D6D on EFEFEF, for a WCAG failing contract ratio of 4.49:1.
Amusingly, the paragraph near the end of the article that begins "Truth is stranger than fiction.." is not flagged as failing.
It's 6D6D6D on FFFFFF, for a ration of 5.17:1. That passes WCAG AA but fails AAA.
In the absence of reflected ambient light, the contrast ratio of black to the dimmest non-black color on an OLED display is infinite, but that doesn't mean black-on-darkest-grey text is necessarily readable, even in a perfectly dark room.
The background is indeed not black, but if it isn't actually white then it's close enough that the text, which i'm sure is indeed mostly actually grey rather than black, shows up well. I've seen worse.
Maybe aside from the unset option, something more specific about a minimum contrast threshold would be useful. Ideally the author wouldn't be breaking below that threshold themselves while explaining it.