I agree. I remember when I bought a refurbished ThinkPad T430 to play with back in late 2016; it came with Windows 10. The interface looked gaudy on the laptop's 1366x768 display, with all of its oversized elements. It seems to me that Microsoft has a penchant for UI designs that consume a lot of vertical screen real estate (i.e., the Microsoft Office ribbon). On the flipside, I've had the opportunity to use Windows 10 on a 4K display at work, and it looks much better on it. It seems to me that Windows 10's UI is designed for high-resolution displays, but the problem with this assumption is that there are a lot of business laptop users out there making do with 1366x768 displays. The old-style Windows Classic or Windows 7 UIs with their conservative use of screen real estate would fit perfectly with these displays, but unfortunately these themes are unavailable in Windows 10, and it still wouldn't address the problem of applications written using Windows' modern UI guidelines.
macOS still looks good on my 1440x900 2013 MacBook Air, and I like how the Cinnamon desktop looks on my ThinkPad T430; I use Linux Mint on that ThinkPad now.
Tip: you can purchase a nice IPS 1080p display for ~110 (EUR)/~130 (USD) at aliexpress. Swapping it with the existing one is ~30 mins, if you are doing it for the first time.
(I've damaged my original 1600x900 TN panel and the quoted price for material was more than the third-party IPS, even without the work. The third party panel is much nicer).
Also related: macOS was originally optimized for 72 dpi; retina at @2x is 144 dpi. Windows (and also Linux DEs) optimized for 96 dpi, 200% is 192 dpi - which is much bigger jump and they look atrocious if the display is in the 140-180 dpi range. That's why macOS can look nice at ~WQHD displays that MBPs ship with, and Windows laptops needs at least 3200x1600 look nice at 200%.
macOS still looks good on my 1440x900 2013 MacBook Air, and I like how the Cinnamon desktop looks on my ThinkPad T430; I use Linux Mint on that ThinkPad now.