Early on the system knew something was wrong with the AoA sensors
Well, to an extent... it correctly outvoted AoA 3 and disregarded it, ironically the 1 correct value.
Why it did NOT tell the pilots ?
The philosophy of what and when to tell the crew is no doubt part of the design and certification. I do note that except for the very latest A320 series aircraft, there is
not an IAS disagree message. Interestingly, there is a (effectively) an AoA disagree, but (in a similar but not identical fashion to IAS) only when 1 ADR has already been rejected i.e. the AoA logic is with 3 values, then reject the anomalous one, when you are then down to 2 and they differ, ECAM Warning (ADR disagree).
I do not know if you fly Airbus, or even any modern complex electronic / FBW aircraft? I would be wary of adding ECAM messages for every failure under the sun. It is quite easy to overwhelm a crew with numerous messages, or just hide down a priority list the real failuire, or solution to it (look at the BA A319 Elec AAIB report, where a single switch selection was required to restore screens, but it was on page 2). Contrary to popular opinion, the Airbus does leave some things to crew diagnosis, since they have the "big overview".
In this we agree 100%
But it is erroneous to state that every situation or accident will lead to a "warning" in order to resolve the original problem
I think we just disagree on whether this accident should have been warned against/prevented?
NoD