CC: "I suspect it's really the A330's interpretation of a complete loss of all air data that caused this accident."
The ACARS reported ADR fail, which could mean any one or more of the outputs of the ADR: airspeed, altitude, CAS, TAT, etc. . The pitot tubes on the A330 feed only airspeed computation, and airspeed is all that had to fail to lead to this accident. Altitude Fail in addition to airspeed fail is really, really tough to overcome. There was probably not a loss of altitude data, and I see no indication there was, except for the TCAS, which could be explained differently.
Do you see any other evidence of Altitude Fail?
GB