As someone who has previously been in the military, I've seen this misconception about Jellico before.
Yes, crewmembers are expected to perform their duties with professionalism, and their is a limit to how much they can openly complain, but a commanding officer should be very concerned about crew morale, even during times of war. A Captain should not be a dictator, but should be interested in feedback from his subordinates about conditions on the ship, as well as the job he is doing.
Ideally, officers should strive to encourage an atmosphere of mutual respect. It's not just about issuing orders left and right, and making unreasonable demands on subordinates.
Jellico made clear that he didn't care very much about the feelings of the senior officers or how the changed work shift orders he gave would affect morale. This is not being an effective Captain who cares about what is going on with the people he serves with.