All boats are different. Even my Dragonfly tri (which is designed to be lightweight) has thicker sections in that area. I have a transducer plug that was cut from the centerline that's an inch thick of solid layup, but the cored areas are very thin skinned (maybe 1/8" on each side of the foam cored composite) but very rigid and don't flex much at all. Experienced boaters who walk my decks have commented on how solid the boat feels.

Then there's the issue about the construction of the layup resin and fibers.