What settings influence Z-Fighting in files with identical geometry? I've 2 sample files: good.blend and bad.blend.
Both have 2 parallel rectangles rotated along z axis and separated by same distance. In fact they're almost the same. However, both were created via different steps.
Why is it that only bad.blend shows z-fighting kind of effect. good.blend doesn't have any such effect.
I tried rotating both in many ways, but only bad.blend shows the z-fighting.
good

bad
One of the parameters that affect Z fight in 3D view window is the distance between clip start and clip end of the camera view. This distance on the  rendering camera can affect Eevee renders also, and should be set as short as possible.