In CoreEnvironmentControllerManager, there's a value called "base_contrast", which is set to 0.1 by default, and gets modified by screen effects, such as taking damage, flashbangs, etcetera.

The effect and intent of this is to highlight the edges of different colors, brightening the overall image, however, this causes an unintended side effect, since this is affecting the 3D space, it causes significant aliasing on those edges.

By reducing the "base_contrast" value to 0 when it's not affected by other visual effects, we can increase the efficacy of Anti-Aliasing, and reduce the overall pixelation around the edges of the image, check the images for examples.