"Unschärferelation" suggests the value coming out of the system (position, impulse, etc) is in a fundamental way not pinned on a single value fixed with 100% precision, but instead it's spread out over a distribution function.
First discussion that happens in an undergrad quantum mechanics class.
Teacher: "It is uncertain" Student: "Can't we measure it better?" Teacher: "No, it is unknowable, no matter what" Student: "Wtf?"
I think "uncertain" is fine. Of course, the particular words are not really that important if you just tell people to read the definitions and equations used in the theory.
Almost all terms in mathematics and science are overloaded in ways like that. For example, what is the "basis" for a mathematical space?
VERY capable physicists have been happy using the term uncertainty principle just fine in English and have no misunderstanding of what that means.
However, this is a really minor nitpick and since statistics is used all the time with QM "uncertainty" is just fine. The article is making a mountain out of a semantic molehill.
One of these hippie types went so overboard that he even made a "hand wavy" coat of arms to go along with his lateral comments about Buddha and Laotze [1] and question our very ability to fully comprehend an objective reality.
[1]: https://upload.wikimedia.org/wikipedia/commons/thumb/d/da/Co...
Or should I not be physics-ing in the morning.