I liked those guys way better than anybody that flew for Biman. Biman people thinks they are on top of the world and everybody is below them.
Unfortunately I would say there is some truth in this post, I have flown as passenger with biman several times, and the experience was quite an unpleasant one, the crew are very arrogant and unproffesional.
Personally I dont know what their training or aptitude for the job is, but its the last way they should be behaving on a failing airline, regardless of what prejudices they have against the sylheti people, who have been keeping this airline flying for decades.