All pixels are a "blur" of R, G, and B subpixels. Their arrangement is what makes a picture look either as designed, or messed up.

For rendering text, on modern OSs you can still pick whichever subpixel arrangement the screen uses to make them look crisper. Can't do the same with old games that use baked-in sprites for everything.

It gets even worse when the game uses high brightness pixels surrounded by low brightness ones because it expects the bright ones to spill over in some very specific way.