The 747 has always been a nice aircraft but, alas, has had it's day. Boeing is just trying to play catch-up with Airbus and not playing very well at all; it's a bit like re-newing the parts in your old car, at the end its still your old car.
Seems to me that all this idiot has achieved is to give a heads-up to every lame brained, pimply faced pseudo software engineer (Hacker) to go out and try their luck. Perhaps one will manage to bring down an airliner somewhere and what happens if they do? Will the investigators be able to determine the correct cause? And if they do, will law enforcement be able to catch the hacker, based on what I see around me today, not a chance in hell.
What about everyone else on the flight? Why should they suffer because two over protective people don't want their spawn watching a movie? At the ages specified, and if they were properly seated, I doubt that they would have been able to see the screens anyway.
If I'm going to Europe, usually Singapore Airlines, Middle East it's Emirates or on occasion Etihad and Thai to Asia. I find it difficult to differentiate between Singapore and Thai Airways, their service is first class and they pay great attention to detail. Emirates and Etihad are both excellent and I can recommend both, but if you are a bit hungry, don't go to sleep, their cabin crew are trained not to wake passengers for meals.