Gladwell based his theory at least in part on Korean Air flight 805.
The NTSB recognized hierarchy as a contributing factor in the crash of that flight. However, in doing so, the NTSB cited a study of US pilots to illustrate problems with such hierarchies and how they can contribute to crashes. Hence, hierarchy problems in the cockpit do not seem limited to Asia. This is further evidenced by the fact that the KLM flight crew in the Tenerife disaster was Dutch.
I'm not sure why you're bringing Confucianism and Korean culture into it. You seem to want to make generalizations. If Gladwell had any statistical training at all, I imagine that one takeaway from his writing would be: Do not generalize from rare events.