Maximum pressure will be on to prove Boeing produced 'a defective aircraft'. It did nothing of the sort. The system worked as it was designed to work. There was a fault in the system. It is beyond human capability to produce a 100% reliable system. You put humans there whose function is to fly the aeroplane AND to take over when the system goes wrong. When the system goes wrong, you simply have an aeroplane with idle power. That your trained humans cannot take over an aeroplane in this state is beyond comprehension. The deepest pockets are the makers, the negligence is on the human airline side. Such faults and events happen every day- power being unpredictably reduced. At the time of design, it was the best that could be produced. I see no failure on Boeing's part. If 3 pilots cannot prevent an aeroplane from crashing because of a minor failure of an automatic system, then they should not have been on the flightdeck, and nowhere near passenger flying!
Where does it end If on an automatic landing the flare system fails and the aeroplane crashes, should the manufacturer be liable because of a faulty system, or the pilots because they did not carry out their function of flying the aeroplane to a safe landing, automatic or otherwise? These pilots had a function to fly the aeroplane, making use of automatics as an aid to human control. They appear to have used automatics as the sole pilot on board! It is time responsibility was accepted where it belongs, not simply where the pockets are deepest!