The FT article has a lack of evidence of an actual operation. It claims Mythos is being used for "offensive cyber operations" in the first paragraph, but doesn't give a source supporting this claim. The lone piece of evidence given says Mythos "would be useful for" infiltrating China or Iran, which is a hypothetical, not evidence of an actual operation.

None of that means the NSA isn't doing offensive work, my issue is that FT claims Mythos is involved in active foreign attacks based on a single anonymous source saying it "would be useful."