605carsten,
the 6ft incident was down to a basic altimetry error. Quite a wake up to realise that for all the sophistication of GNSS, PBN and RNP, an ATC screw up and lack of crew awareness could nearly bring the house down.
Could a sim scenario train against this? You bet.
Basic flying skills still matter and show. The AFCS requires more skill, it isn’t a substitute. Both need to be trained and tested.