The sky lighting, sky vibrancy, cloud intensity (white level), car body, car windows, chrome and general reflections play the biggest role in getting close to the Uncanny Valley level, far more so than any of the other settings. If anything, the taxi and its reflections are what pull the whole image together. Those screens are taken at during the non raining overcast weather and at a very specific time of day and the modder even says in his ReadMe file that you need to download a certain taxi model and then adjust the color and reflections before you can get it looking like his screens. It looks dull with not enough lighting, colors are too dark. I downloaded it direct from your post and installed it on a clean install of gtaIV 1.4 and in the exact same part of the city, it looks nothing like those screens.
