Habits and attitudes are inculcated very early on methinks. What stall training did these pilots have when they were training to be commercial pilots?
Are you trying to imply that somehow they were awarded a CPL without stall training? It is really ridiculous that some on here are trying to imply that they couldn't recognise a simple stall. Clearly there were was a lot of confusing feedback in the cockpit.
FWIW, the French CPL syllabus contains a great deal of stall training - full stalls, incipient stalls, stalls in the turn, stalls in different configurations, stalls without airspeed reference, stalls at constant deceleration, all under the hood. But as others have pointed out, recognising and dealing with stalls in a light aircraft is a very simple matter compared to in a complex heavy aircraft at altitude.