Old Fella,
He was instructed to descend 2000 feet for traffic conflict. He demanded to know the reason, the controller politely explained the options; either CX would have to descend, or two other aircraft would.
The CX pilot then demanded to know what the other two aircraft types were. On being told Airbus, he then asked their destinations, US west coast, and then gave the controller a mini-lecture on 'big' aircraft vs 'little' aircraft fuel burrns.
Arrogant and condescending in the extreme.
As informed, he was brought back up to his original level ten minutes later.