Whether floor-to-ceiling windows diminish privacy certainly also depends on the location and the property. I wouldn’t now place the fully glazed Huf house within a building zone 3 meters from the sidewalk on a busy street.
But if, for example, the entire garden is separated by a 1.8m high wall and there is already natural screening to the front towards the street through old trees and bushes, then the upper floor is designed as a recessed top floor and is therefore already shielded from view and by the parapet, and lastly all the windows have venetian blinds to provide additional privacy if needed without absolute darkness, then it works.
Well, one could still apply full-surface black film to the windows to top that.
And regarding furniture: Hopefully everyone is clever enough during the planning of the house to keep not only the exterior architecture but also the interior architecture and later interior furnishings in mind. We have drawn and cut out our existing furniture as well as the kitchen to scale with their areas, and then placed them on the floor plans of the house to get a first impression of whether it fits roughly. Without the kitchen island hitting a floor-to-ceiling window.