In terms of form follows function, I think Amish furniture is an excellent example.
There are no purely decorative parts, but the necessary functional parts are clearly visible.
That cabinet is gorgeous. But it does have some decorative elements: note the dovetails between the rail and stile in the upper doors, a dowel or splined, thru-mortise would have worked as well. Also the angle of the upper rail of the doors. These took more time.
Man yearns for more than mere function, this is the basis of minimalist’s failure.
Not sure about I.M. Pei’s failure with the Nat. Gallery. I think he he believed his structural materials would compensate for expansion. His refusal to change the design based on this experience is another matter.