If you actually read the article you'll find out that the properties of the lichen could not be explained by the two known elements alone, that there was some other factor that nobody could describe. The careful work done here uncovered a third element that was the important difference, that there's a three way symbiosis. Now they have a complete model of what's going on after an initial hypothesis put forward 150 years ago.
Considering someone's finally explained how these types of organisms work, and it's a large branch of life, this is a pretty major breakthrough.
And that's why you can't trust them. (cue rimshot SFX)
But lichen... You know, now that we have a functional understanding of their biology, I'm quite excited to see what this new knowledge will yield when applied. Pharmacology, materials, food production/processing — "We don't know what we don't know," but having more data helps us to learn what questions we can ask.
Anyhow, thats just my perspective. No offense is intended here. This is solid, important work. I'm just quibbling over the headline.
(If your argument is that "overturning" should never be used to describe a scientific breakthrough you may have a point, albeit a rather uninteresting one.)
On the other hand, figuring out why we've been failing to grow lichen by merging the two species manually for the past century and a half is definitely a job well done. :)