I'm not sure it's fair to say nobody knows how to fix this. A straightforward solution would be to record a couple thousand mouse paths of varying distances and base your script's mouse movements off these. Example: I need to move my mouse 70 pixels, I grab from my thousands of human mouse paths some that are around 70 pixels, say between 40-100. I grab one of those paths, stretch it or shrink it, add some noise to it and use that path to move the mouse.
The downside to this is it requires a fair amount of work recording that many mouse paths and realistically is easier to do and probably better for not being "detected" if done by each scripter individually for their own scripts.