The Neutrik ones are a standard size to fit a panel system. There's that much space because they're also the same size as XLR microphone connectors. With the advent of mp3 players, I'm sure they were designed to fit in spots that would have normally held microphone inputs.
I'm not sure if that's the beef. I'm reading into it that it's not the size of the mount but the empty airspsace around the socket itself.
The first image has almost no airspace and the plastic molding is brought almost flush to the connector.
I always assumed there is some sort of jacket or sleeve on the male end that fills this airspace, like a locking connector or a water zealing boot. I could be wrong, I haven't done stage work in years.