Is that an "Airbus" design or an "Industry" design, i.e. same situation or comparable airliners (Boeings, Bombardier, Embraer...) ?
This is, I think, a question that was never answered.
It is a ADIRU issue, no airliner is supposed to be capable of flying! at 60 kt or less.
ADIRU ARINC Air data output is set to AoA NCD(No Computed Data) to the subsystems (e.g. FWC) at 60 kt or less and air speed output NCD below 30 kt or less.
IIRC Boeing T7 ADIRU sets NCD <30Kt and SAARU <50 kt-
"Airbus" design offered several options like analog AoA indicators and/or BUSS (AoA output thru IR part of ADIRU i.s.o. Air Data part).
It is up to the operator(pilots?) to select such an option or not!
Link to AF BUSS