The one about green where it recommends shifting it blue or yellow made me recoil, like shut the article down as fast as I could because the one they suggested was a revolting bile color. Sure, I absolutely respect the power of color theory, but this article was kinda heavy handed and most of the examples just really rubbed me the wrong way, like why is virtually every example just desaturated and low contrast to make it a sickly gray, and why does some of their advice contradict later advice (especially regarding contrast)?
If you literally recoil from a colour choice you are probably far at some end of the bell curve and this article is not suitable for you, but that doesn't mean it's wrong.
They have the right idea with the theory, but there's some nuance in proper execution. If I learned anything from photography, it's that the best adjustments are barely on the edge of perception.
If you averaged the before and after examples (allowing that the "average" of colours is a complicated subject in itself), they would probably be pretty good.
That’s strange because I care a lot about color, datavis, and generally agree with these types of articles.