I think the main issue here is that we have crews flying around who are utterly reliant on the information given to them by outside agencies and the pretty pictures on the ND and PFD.
A miss set QNH can kill during an NPA as nearly demonstrated by this event. If a crew builds their SA from scratch in a robust manner they will pick up a mis set QNH by comparing it to the ATIS, by checking what the baro altimeter reads when the rad alt comes alive and latterly by realising they are too far from the field as they pass 500radio, 100 radio etc.
This crew was dependent on the pretty vertical profile displayed by the avionics which was incorrect.
Build your own SA, and place traps in your procedures to detect mistakes.
LD