The fact that you can see the hull of the ship is what gives it a window effect. Without that, it would seem more like a typical viewer just with some additional images overlaid.
You can see the hull. It is somewhat visible. The first sixth or eighth of the viewer window shows the hull. You can clearly see "NCC"
Yeah, that's what I said, you can see the hull of the ship. That's what gives the impression it is a window and not just the viewer showing space with some random read-outs on top.