When Windows XP came out, computer magazines wrote articles on how to switch the more modern, colorful UI back to the old, grey, drab, boring UI of Windows 95/98/2000.
I was young at the time and this seemed absurd to me. Why would you willingly use a UI that looks like wearing an old grey tie for a dusty office job in a depressing concrete building?
I was youngish at the time and thought Windows XP looked like clown vomit.
There is a German saying "Grün und blau schmückt die Sau" ~"green and blue grace the pig" - and XP was green and blue and shiny like hard candy.
Yeah, it was butt-ugly. The default Windows UI didn't actually look better until Windows 7, but I used the "Classic" look as long as it was supported. I skipped Windows 8/8.1 entirely, and while Windows 10 was reasonable in terms of how it worked, it was also butt-ugly, but now you couldn't do much of anything to customize it.
Windows XP was the first OS I ever used and still I switched to the classic UI because it looked just better in my opinion.
The older UI was also noticably faster. The new UI looked like a daycare: saturated colors and all thick, rounded borders on everything.
Some people like brutalist architecture.
I think is so ugly that I'm half tempted to chatgpt fact check this comment. It very well could have been a deliberate conspiracy to lie to the public and say it looks good to make some austerity go down easier.
I hate brutalist architecture, but love the Win2K design language, for what should be fairly obvious reasons. I interact with software. I don't interact with architecture beyond the visuals. It can look as shit as it wants, but if it gets out of my way and lets me do what I want to do, then it's great. It'd be nice if it look better, but I'll take function over form 10/10 times.
The only reason brutalist buildings were made in that style is because it's cheap(er), and because some architects started to smell their own farts a bit too much. Win9X/Win2K were made the way they are because it's actually conducive to get shit done.
Making the UI grey seems just as conducive to productivity as the raw concrete walls on a brutalist office building.
If you were to quiz people who preferred the Windows 2000 look, you would more likely get detailed answers regarding the design language and functionality. If you were to quiz people who preferred the XP look, you would more likely get answers revolving around colors and shiny.