I think, in general, UIs back then felt more "human": soft, intuitive, yes, sometimes a bit clunky, and yes, sometimes with contradictions (like any human being). Now they feel more "robotic": harsh, darker (or is it that designers nowadays tend to use softened colors?), precise as any machine (but this doesn't always mean that they are easier for humans to use). Robotic, though, doesn't seem too far off: society is becoming more and more robotic I believe.