I find it hard to forgive Airbus (or Boeing for that matter) for allowing a stall indication to stop because the the A/C IAS has decreased below a certain amount.
No real arguments about your post until the sentence quoted above. The manufacturers A or B do NOT expect properly trained commercial pilots to HOLD an A/C into a FULLY developed stall. Especially having given them all the warnings prior to the stall, which you were also alluding to in your comments. So we cannot really blame the manufacturers.
It was not just because the IAS went below 60Kts but the AOA was also outside limits. Flight testing into the fully developed stall is not carried out so they do not know how the interrupted airflow would affect the various readings.
Hamster wheel again!