Falling under the category of cessation of stupidity disguised as innovation we have fiber-optic retrofitting of airplanes.  Yes, that's right, every wire on almost every commercial airplane is insulated copper.  Over 100 miles of insulated copper per plane.  Insulated copper that is heavy, prone to fire and electromagnetic interference, and difficult to track problems with.

Why oh why have we done this to ourselves. An industry that cut the lettuce out of its meals to save weight didn't think of changing over to fiber optics which would save hundreds of pounds while making planes safer and easier to maintain.  Well, they're doing it now.  All of Boeing's next generation planes will be using optical communications, saving hundreds of pounds and thousands gallons of gasoline.