My problem is that I have overseen a lot of people that are working night shifts monitoring boring equipment. To me, that isn't much different from an aircrew flying across an ocean. When I oversee these people I encourage them to watch TV or do something like that.
Now, I'm able to do that because I always design systems to notify the teams of a problem and I would prefer that they be awake to receive that notification and I see that as more likely if they are watching a movie.
Could that be extended to the cockpit? I would think so, but experience has shown us otherwise.