https://www.dell.com/en-us/shop/dell-laptops/dell-15-laptop/...
It is very, very common. Just not in the Mac world.
1920 x 1080 51.89%
2560 x 1440 21.20%
3840 x 2160 5.00%
To me, it's more about what I'm used to. I have a perfectly fine several years-old monitor, so why should I throw it away?
Other way around, most Mac software is not tested how it behaves on inferior external monitors.
Mac OS X 10.4 tried the same thing (Quartz2D scaling) and it was so damn difficult that they threw it out and went for simple 1x/2x/3x auto-scaling. Even 3x was a challenge because of pixel alignment.
>Have you ever tried to write HiDPI-aware Win32 code?
I haven't. I don't think there's any reason to, I'm more of a wxwidgets fan. I don't think even Microsoft makes applications in raw WinAPI.
>I suggest enabling HiDPI in Control Panel sometimes and marveling at how many Win32 apps just don’t notice and draw as postage stamps.
The default behaviour of a DPI-unaware app in Windows is to scale everything by the scale factor. Which - yes, looks completely awful and blurry, but that's not what you describe.
Edit: Guess it depends on the app