Once again it comes down to human factors - know your machine and how to deal with issues. This was lacking. No aircraft is perfect and despite the current machines being far superior to previous machines they can still go wrong and have their foilbes. Pilots need to understand this and to be able to react correctly when it happens. Those that don't crash. You mention denial and this is certainly a factor but the very fact of denial is rooted in the mind of the denier. You are right that pilot error is far too 'glib' an explanation for the accident but it was a recoverable problem if the pilots had been able to react in the correct way.
OC, Human Factors?
How well trained were the AF447 crew to handle UAS at altitude. Judging from the horrible example we have been puzzling over the last 2+ years, they were not adequately trained for the
successive situations that they encountered. Whatever the emphasis of the training program, it did not prepare them for what they encountered.
I'd like you to think (way?) back to when you were learning to fly. Did you ever get in way over your head? Do you remember that feeling? Did the instructor steady things up for you and allow you to resume control? Were you lucky (if solo) and puzzle things out for yourself?
These guys got in way over their heads. There was no one there to punch the freeze button and explain what went wrong. To their credit, they kept on trying to the end. Unfortunately they did not understand that which is perfectly clear to us using our retrospectiscope.
The purpose of training is to keep us from getting in over our heads. As you fly, you will periodically find little things you didn't know or did not properly understand. Some of these are of minimal import. A few can be life threatening.
When training departments decide what to emphasize, there is a risk assessment of some type used to allocate training effort. Most accidents seem to occur in the takeoff and landing phase. Very few in the cruise phase. This accident unfortunately occurred in a less emphasized phase of flight. Furthermore, the system failure, UAS, had only recently begun to be visible in the safety radar scope, so training in that subject had to displace other training to be included in the time-limited training syllabus.
To sum up, the crew of AF447, particularly the two co-pilots were not ready for the UAS emergency that they encountered. They handled that emergency about as well as you would handle a night landing aboard an aircraft carrier.