The friend was being somewhat simplistic to you. That's not one of the reasons, especially on the Airbus FBW. Today's aircraft are not more complicated to handfly compared to those 50 years ago.
The skills and proficiency missing to save AF447 from its fatal end were not those you could learn or master by flying without the autopilot in cruise.
There is, however, a recognized industry initiative to adress those missing bits, look for "high altitude upset and stall recovery training", or similar. The key obstacles before tangible benefits are obtained are:
- lack of a precise mathematical model for the simulators;
- cost of the training.