The cinematographers for The Pitt employ a subtle film grain to evoke a sense of realism and documentary-style intimacy. Grain is notoriously difficult for encoders because it represents random, high-frequency data. A poor encoder will try to smooth this out, washing away the texture of the image, or try to preserve it, ballooning the file size.
In the opening scene, as the camera tracks Robby walking down a dimly lit corridor, the gradation of the shadows on the walls remains smooth. Even at lower bitrates (around 1500-2000 kbps for 1080p), the libvpx encoder maintains the intended atmospheric gloom without the artificial sharpening that often plagues hardware-encoded streams. the pitt s01e13 libvpx