The premise of the article has some weight, but the final conclusion with the suggestion to change the icons seems completely crazy.

Green meaning "to the best of our knowledge, everything is good with the software" is well understood.

Using green to mean "we know that this doesn't work at all" is incredibly poor UI (EDITED from "beyond idiotic" due to feedback, my bad).

And whilst flaky tests are the most problematic for a CI system, it's because they often work (and usually, from my experience most flaky tests are because they are modelling situations that don't usually happen in production) and so are often potentially viable builds for deployment with a caveat. If anything, they should be marked orange if they are tests that are known to be problematic.