Why are 4 engine civilian turboprops not produced anymore As per subject why are 4 engine turboprops not produced anymore for civilian flights if turboprops are so efficient?

How comes the military still use them (see Airbus A400 and C130)

It would be amazing to fly on a 150 seater powered by 4 propellers.

What favours jet engines?
Well, military turbo-props are supposed to carry a large load at lower speeds, they wouldn't work well in passenger airplanes now because a jet plane can carry the same amount of passengers for a longer distance and faster than a turbo-prop can. However, they still use double-engined ones because they fly short, low-density routes to save money over using larger jet planes.