Looking at the Nagaoka camera you linked to, I can imagine it being used for many other things than just portraits. It's even portable enough to take outdoors. Certainly, still-lifes and product shots in the studio are not out of the question.
And, swings and tilts, especially with a long lens and a wide aperture, are really handy to place the plane of sharp focus where you want it to fall on your subject. Someone sitting at an angle to the camera and looking back at it may need swings to have both eyes/shoulders/etc., in focus.
Best,
Doremus