This subthread is an illustration of the HN tendency to seize on whatever aspect of the article we think we can sound smart about, which, despite seemingly being an isolated comment that the scientist did not clarify or expand on at all, the journalist cleverly elevated to the headline.
Very good observation
You've just summarized the beauty that is n-gate.
That it's in the title?
GP is pointing out that it's being used incorrectly
except that, this being the Internet, the observation is not in fact correct.
(I think we've all been "guilty" of this at one point or another)
The term isn't used incorrectly
Black Swan event is always unexpected, unpredictable, with no prior recorded history of such event, so no one could prepare for such event. It's always catastrophic as a system couldn't be possibly ready for it.