Another tack on the fatigue issue is the long term effects on health caused by constant long duty periods which disrupt the normal sleeping pattern etc.
I suspect in the years to come we will see more and more pilots losing their medicals or having to retire early due to health issues. And that's before we mention the affliction which is rarely mentioned viz. mental illness.
I see the convergence of many factors in the airline industry and the debilitating effects of constant and never ending disruptive work patterns is certainly one of them.
This will be an interesting one. Years ago there was a perception that pilots died young. We all knew of guys who croaked in mid-60's. It was conjectured that pressurisation, radiation, sleep disturbance, lack of exercise while at work, disrupted eating habits, bad or no balance between work & social life etc.We wondered why guys with a medical every 6/12 months then keeled over quite soon after retiring; and this was for guys who retried at 55-ish who should have looked forward to a reasonable life style & pension. Are some investigation we were told the death age amongst retired pilots was national average.
Now, with guys working quite a different life style, flying until 65, retiring to a hopefully reasonable life style, but with no or very little company pension, it will be interesting to see if the death ages change. Too early yet, but no question the strain of the working life is far greater than it ever was, and more much longer.