UI design doesn't get much better than what Windows 95 introduced, if you're talking about navigating efficiently. Later on some UI elements were introduced that helped speed up controlling applications. Starting from Windows XP it started to go downhill. Fortunately, you were able to select 'Classic' UI on these modern versions, which made a perfect combination, until it was removed from Windows 8 (or was it 10?).
This is all due to the hordes of under-educated people who call themselves UI designers, combined with clueless self-proclaimed software developers from ever lower wages countries. Blame it on corporate greed.
As for Science; several renowned institutions have done usability research in the 80's to scientifically support what some people already intuitively knew, but what "UI designers" seem to not get.
The people who intuitively got it were working at Xerox PARC, developing the Xerox Alto in 1973.
Famous Jakob Nielsen quote: " I can just barely understand companies that ruin their user experience because they don't want to pay $298 to find out what the usability research says."