About the lost infos due to Unreliable Airspeed.
The characteristic speed function (see above) computed by the FE (Flight Envelope part of the FMGC) is lost, meaning that Speed limits, computed by the PRIMs (FCPC), are also lost, including Valpha_prot (Normal) and VSw (Alternate).
Two other functions, displayed by the Primary Flight Display (PFD) were also lost (flagged, see ACARS): Both Flight Director (FD) and Flight Path Vector (FPV) were flagged. This is very bad as the FPV would also provide a visual form of AOA via the Flight Path Angle:
