My hypothesis is today's "modern" OS user interfaces are objectively worse from a usability perspective, obfuscating key functionality behind layers of confusing menus.
It reminds me of these "OS popularity since the 70s" time lapse views:
https://youtube.com/watch?v=cTKhqtll5cQ
The dominance of Windows is crazy, even today, Mac desktops and laptops are comparatively niche
These kinds of things almost always give me an uncanny-valley feeling. Here I'm looking at the screenshot and can’t help noticing that the taskbar buttons are too close to the taskbar’s edge, the window titles are too narrow, the folders are too yellow, and so on and so forth. (To its credit, Wine is the one exception that is not susceptible to this, even when configured to use a higher DPI value so the proportions aren’t actually the ones I’m used to.) I’m not so much criticizing the theme’s authors as wondering why this is so universal across the many replicas.
The problem is that the interfaces these bootleg skins draw "inspiration" from were designed on the back of millions of pre-inflationary dollars' R&D from only the best at Golden-Age IBM, Microsoft, Apple, etc.. BeOS, OS/2, Windows 95-2000 do not look the way they do because it looks good, they look the way they do because it works good, countless man hours went into ensuring that. Simply designing an interface that looks similar is not going to bring back the engineering prowess of those Old Masters.
As a (weak) counterpoint to supplicating ourselves to the old UI masters, I submit Raymond Chen’s observations from 2004[1] that the flat/3D/flat cycle is largely fashion, e.g. how the toolbars in Office 97 (and subsequent “coolbars”) had buttons that did not look like buttons until you hovered over them, in defiance of the Windows 95 UI standard. (Despite Chen’s characteristic confident tone, he doesn’t at all acknowledge the influence of the limited palettes of baseline graphics adapters on the pre-Win95 “flat” origins of that cycle.)
Also worth noting are the scathing critiques of some Windows 95 designs[2,3] in the Interface Hall of Shame (2000). I don’t necessarily agree with all of them (having spent the earlier part of my childhood with Norton Commander, the separate folder/file selectors in Windows 3.x felt contrived to me even at the time) but it helps clear up some of the fog of “it has always been this way” and remember some things that fit badly at first and never felt quite right (e.g. the faux clipboard in file management). And yes, it didn’t fail to mention the Office 97 UI, either[4,5]. (Did you realize Access, VB, Word, and IE used something like three or four different forks of the same UI toolkit, “Forms3”, among them—a toolkit that looked mostly native but was in fact unavailable outside of Microsoft?..)
None of that is meant to disagree with the point that submitting to the idea of UI as branding is where it all went wrong. (I’ll never get tired of mentioning that the futuristic UI of the in-game computers of the original Deus Ex, from 2000, supported not only Tab to go between controls and Enter and Esc to submit and dismiss, but also Alt accelerators, complete with underlined letters in the labels.)
[1] https://devblogs.microsoft.com/oldnewthing/20040728-00/?p=38...
[2] http://hallofshame.gp.co.at/file95.htm
[3] http://hallofshame.gp.co.at/explore.htm
It's right in the second sentence: "...Windows 1.0, which looked very flat because... color depth was practically non-existent."
I think that's because they used the stock UI toolkit of the original Unreal Engine, which also had all these things. If you recall, UT'99 actually had a UI more like a desktop app at the time, complete with a menu bar and tabbed dialogs:
http://hw-museum.cz/data/article/VGA-Benchmarks/Benchmark-VG...
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