This point feels a little strained. There is a question: "Was autopilot in use?", and an experiment was performed to answer that question, which produced an informative result, which was reported. You seem to be attacking the linguistic structure of the statement by interpreting "coudn't" to mean some kind of existentially inviolate truth and not just... the result of the experiment.

I mean, come on. This is what people were saying within hours after the crash: autopilot as shipped simply doesn't have behavior consistent with this accident. It won't command the accelerations that would have been required on that tiny street and (as measured by the NTSB) won't even engage in that particular environment.