Better for a building's inhabitants to be free to bring their own life and color, than for the building to try to impose one decade's view of life and color upon every generation for the next century.
And isn't the complete absence of any kind of style, color, or pleasant features in general, an imposition of a specific view in itself?
And finally, is what you describe even a problem? How many people living in old Art Deco skyscrapers are miserable and trying to leave due to having a century-old style imposed upon them? Or people living in historic neighborhoods? Whereas featureless gray cubes "free them to bring their own life and color"?
As for gray cubes, you can shine any color or pattern of light on them you want.