This is why you should make another steam.
(Searching up your YT name on steam leaks this name, as it was a prev name.)
(I am a teenager, and just wanted to let you know how I got here. This will not be public info.)
essentially, it just makes it so that things always look pixelated, rather than, as an example, when the zombie's head falls off the pixels rotating, they stay the same direction, while the head rotates, mimicking the way that the game used a console that had the zombies pixel-accurate.
(as an example, download shaderglass and set the shader to 'none'.)