How to reproduce:
1. Open the “IN-92140_DitherNodeBug.zip“ project
2. Open the “DitherNodeBug“ Scene
3. Enter Play Mode
4. Observe the dithering effect on the Sphere in the Game view
5. Select “Settings > PC_RPAsset” Asset in the Project tab
6. Change the “Quality > Render Scale“ to 0.51 in the Inspector
7. Observe the dithering effect on the Sphere in the Game view again

Expected result: Dithering is pixel-sized
Actual result: Dithering is blocky

Reproducible in: 2021.3.47f1, 2022.3.56f1, 6000.0.34f1, 6000.1.0b1

Reproduced on: Windows 11 Pro (23H2)
Not reproduced on: No other environment tested

Note: It seems only the dithering with “Default“ and “Tiled“ Screen Position is affected while the others keep their normal dither sizes