The Aeroperu 603 crash had something AF447 doesn't (yet).
They had recovered a piece of the fuselage that had speed tape covering the static ports, done to protect them during an aircraft wash. That was THE smoking gun. Case closed.
The crews' actions (and the planes' responses to crew input) were entirely consistant with the blocked static ports. The possibility of a triple redundant failure (all 3 static systems), was unheard of, and was never trained for, or even discussed. But it happened. If it had been during daylight hours, perhaps the tape would have been spotted in the walkaround, or a horizon would have been seen and used by the crew out the window.