I am really surprised this didn't kick up

I must have missed the part about wings breaking off. Aircraft are inspected for cyclic fatigue so as to preclude material failure. Airplanes normally crash because of terrain interference with the flight path or operator error, hardly ever for material failure.
Yep, you want some flex in an aircraft structure. That is for certain. With x ray inspections performed on critical structural points at certain airframe cycle numbers in an airframes lifespan to detect issues before failure. The reason most of em end up at the scrap yard to be cut up, is they reached their cycle limits for the airframes projected lifespan as set by the manufacturer.

Most crashes are caused by pilot or air traffic controller error, incorrectly packed items in cargo compartments causing a fire, acts of God like lightning strikes, bird strikes etc. and software issues. For awhile though the biggest was CFIT. Controlled Flight Into Terrain. That's because aircraft only had altitude indicator pingers that went straight down. Now they use an antenna pinger that looks fwd and down. I am pretty well versed on airline crashes, and causes. A lot of them could have been prevented. The FAA investigators when they find a cause work to have the U.S. fleets and aircraft manufacturers update the aircraft or change procedures that caused the crashes in the first place.