Resampling you can choose. Display Properties > Settings has a new Resampling box: Lanczos (crispest), Cubic spline (Catmull-Rom, the default), Bilinear (soft) or Nearest (blocks). It decides how the desktop resizes its own artwork when the scale is a fraction: icons enlarged from their art, the XP and Windows 7 window chrome, the mouse pointer, the Snipping Tool's view and Imaging's picture -- and, at any scale, how the wallpaper is stretched, fitted, filled or spanned (the Windows 2000 shell used nearest neighbour; that is still on the list). Whole-number scales stay exact pixel blocks whatever you pick.
The resampler is separable and phase-correct, works in premultiplied colour so transparent edges stay clean, and widens its kernel when shrinking.
Why it is not on the Screen method. The X server's own screen stretch cannot take a better filter: its "good" and "best" are bilinear, and its convolution filter is a fixed kernel with no sub-pixel phase, so it can only blur a nearest-neighbour picture. The probe that showed this is written up in docs/SCALING.md. For the sharpest fractional screen, use the Sharp method from 1.13.0.
curl -sL jacktulli.github.io/w2k | sh