In a car banana plugs would come out.
There was an attempt to make the Neutric Speakon connection the standard for speaker connection. That would have been a very good connection. I'm pretty sure there have been legions of units blown up by the current screw/banana plug connections. However, again it was receivers causing this failure of adoption, as the manufacturers did not want the expense and said there was not room.
Some banana plugs expand and some have a sleeve that compresses when inserted, but they cost more and manufacturers are more interested in lowering cost. In a car audio situation, banana plugs take up too much space and unless they insert at a right angle to the face of the amp and are very short, it can mean the amp won't fit into the space available.
Commercial/industrial equipment uses Phoenix (also called 'Euro connectors') for inputs, outputs, control signals, etc- these aren't glitzy enough to interest the audiopiles who want their connections to involve something that almost nobody has heard of, can't spell or pronounce, or afford. The one thing that would annoy them most- they ALWAYS work and I have yet to see one work its way out of the receptacle on its own.
Speakon are great, but they take up a lot of space. Also, with the "I make my own cables" crowd, I suspect many amplifiers would fry because they didn't quite understand the locations of the terminals on the back side.
