..For the majority of us,listening to the video audio in post #1, it sounds an appalling lack of SA...plenty of clues,after the initial mistake...( which we all can,and do make)
When do we need to be giving our utmost attention to ATC..I would say,obviously at all times,but especially in climb and descent....
"They may have been distracted"!..huh..that is what the simulator is supposed to teach us...
To me this is about discipline...and,how not to operate...and I'm mister average,trying to improve...
And,lets not get on to the subject of the ever increasing omission of the words,"Flight Level"in climb and descent clearances,by both pilots and controllers.
I'm guessing that there is an ever increasing lack of imagination of what can go wrong,amongst us!..Frightening!