

Those are, as the name suggests, the same graphical elements but designed at twice the horizontal and vertical resolution. When you run 200% scaling, which in the case of a 4K display would be "1080p equivalent" (since 4K is twice as many pixels in each dimension compared to 1080p, and 4x as many pixels overall), then macOS and any Retina-aware applications instead use their art assets. When you run unscaled 4K, macOS and applications use their standard art assets, designed for unscaled, non-Retina display scenarios. But running "scaled 1440p" will erase some of those benefits. That said, macOS and its applications tend to handle scaling quite a bit better than Windows because Apple implemented a design that made it VERY easy for their developers to support display scaling (one of the many perks of Apple having control over their OS and most of the hardware it would be running on). On the Windows side I've always considered 27" 4K displays to be the worst of both worlds, because the pixel density is high enough that you have to enable scaling - which many Windows applications still don't handle well - but not high enough for a true Retina experience, which requires 5K on a 27" display. 1440p is ideal.which is precisely why 1440p was the standard resolution on 27" displays before 4K mania set in thanks mostly to TVs. I agree that "sharp 1080p" would be huge on a 27" display and unscaled 4K is too small.
