In the linked Netzpolitik article (in German) it's pretty clear that the 90% refers to Precision (i.e. 90% of flagged instances are True Positives), not accuracy. Still, the article (and probably the primary documents as well) do a horrible job of differentiating such concepts.
[For clarification: Don't understand as my post as an argument for Chat Control, please :)]
snovv_crash|3 years ago