Beyond that Windows NT's interface is just perfect. And TBH none of the above are really essential, just small quality of life things. But even without those i'd be fine.
I think modern Windows add too many little distractions with icons, notifications/popups, gadgets, etc everywhere.
Also the classic theme. I want that back. I run Win7 with the classic theme and Windows 9x/NT4 color scheme (the one with the soft light in the 3d elements, not the "Windows Classic" in 2K/XP/Vista/7 which lacks it - i had to import the colors through a reg file from NT to get them) and i like how it looks. I used Win8 and Win8.1 for a while and ran a hack that disabled theme files (which forced Windows to fallback to the classic theme) but that broke Metro/UWP apps. It wasn't an issue with Win8.x but Win10 uses UWP apps everywhere and it becomes unusable. It might sound a frivolous reason, but i reverted back to Win7 because i don't like how newer Windows look like.
Since i don't expect Microsoft to do any of the above, my long term plan is to make my own environment that looks like Windows NT 4 in Linux :-P.
User experience is important. Would be like a car switching the positions of the Gas/Brake pedal.
UI matters.
But, honestly, comparing to something like Windows NT 4.0, I can't really say, why Windows 10 is better. There might be tiny things here and there, but overall experience is similar. The only Windows releases I remember were those particularly bad (Vista, 8) and those, which accumulated large userbase (XP, 7). Other than that, I don't see much progress. If Windows NT 4.0 would be supported today on current hardware and software, I'm not sure if I would use anything else. It was good enough.
May be those only my memories, I don't know.