The title is misleading. The message is really:
Stop using unlabeled icons in data tables.
It says, "Norman Nielson argues that text + icon has the highest cognitive recall and lowest error rate"
Here's what the Nielsen Norman Group says about Icon Usability: https://www.nngroup.com/articles/icon-usability/
The conclusion: "Always include a visible text label. As Bruce Tognazzini once said, 'a word is worth a thousand pictures.'"
Here's the quote in context: https://www.asktog.com/columns/038MacUITrends.html
"In 1985, after a year of finding that pretty but unlabeled icons confused customers, the Apple human interface group took on the motto 'A word is worth a thousand pictures.' This still holds true."
I took away from the article that I should probably get rid of icons in data tables.
I think the reference to Norman Nielsen was confusing. At the end of the article the author likens icons to visual speed bumps in a data table. The implication being to avoid them or at the very least use sparingly.
WCAG is a standard designed around the web and web-adjacent apps. Am I missing something here? Because accessibility standards are much easier to adhere to now. So the text label always has to be there, but you can also make it visible in the design and it's accessible by default.
This is a lesson to be learned by people who want minimalist UIs.
It should be noted that the example given by the OP contains ‘poor’ icons which are more a consequence of the nature of the source - i.e. a HR headshot does not an effective workflow make ..
The problem for me is when an icon is repeated many times on a page, such as once per row. The word quickly becomes redundant, and the repetition looks ugly. Tables are supposed to be information-dense and wasting screen real estate interferes with the user's task.
I haven't found a good general solution to that. Hover doesn't work on mobile. A legend map is hard to locate. "Expert mode" introduces new problems.
Sometimes I'll just use an unlabeled button and make whatever it is undoable, so that users can just click and discover. But that's hostile to completely new users.