For example, twin engines are statistically safer than more engines, and Boeing had to lobby the FAA to allow them over water.

For another, Boeing wings do not have hydraulics that extend past the engines. Torque tubes are used to transmit power further. This is so that a major engine failure won't damage the hydraulic system. This was not a requirement until a crash from another manufacturer's airplane was due to such damage, and Boeing airplanes were not susceptible to that failure mode.

Your theories about how the industry works are speculation.

The twin engine statistics story that you cite is not the story that I remember for the 777.The FAA had rules which were based on the behaviour of old engines and dictated that an twin engine aircraft should be a smaller distance from an emergency strip than was possible for the best routes across the major oceans (I believe it ruled out the Pacific routes completely). Boeing demonstrated (successfully and correctly) that modern engines failed so rarely that the four vs two distinction was obsolete.

What has happened in recent years is that another failure mode has emerged, it's a complex one due to pilot training, HCI and the vulnerability of automated systems to failure in modes where common sense knowledge could protect them. I expect and believe that the systems and institutions of the aerospace industry will be fully strong enough to manage this, but I don't think that this is the case for many other industries that are beginning to experience the same sort of problems - notably self driving cars and computer medicine.. Many people think differently - the test of theories is time, so we shall see.