Comment by Etherlord87

This kind of problem appears also with floats, just later with 32-bit floats than with 64-bit ints.

And the solution to this problem is to adjust your coordinate space, e.g. make every nanometer represented as `1` but have the containing object matrix have scale fields set to 1e-9.

So this is not a theoretical problem, just a practical one: the z-fighting you get with floats, would happen much more often with integers - you absolutely can avoid it in both cases, but practically 3D engines are designed with performance in mind, and so some assumptions lead to limitations and you would get more of them with integers.