There are some practical reasons but safety is certainly one. Unlike cars, the lifespan of an airplane is usually measured in decades. Not saying it's impossib

There are some practical reasons but safety is certainly one. Unlike cars, the lifespan of an airplane is usually measured in decades. Not saying it's impossible, but you can't demand we redesign airplanes overnight to add a bunch of weight and complexity for a fleet that was mostly built in the 1950s-1970s. I would also note, I am a shade tree mechanic and work on a lot of cars, the #1 source of failures in modern cars is almost always complicated emissions control systems, so it's a harder problem than it looks like.