Somethings unfortunately completely broken in this game then, I've tested in every possible way now; script, manually moving the mouse and using a 100% accurate machine to move the mouse. And aside from some slight smoothing issues in Star Citizen the calculation is spot on here. The smoothing issue is that very small movements will not register or be too short (even with smoothing/acceleration set to 0 ofc). It shouldn't affect a normal 360 swipe in any significant degree though.
I have currently no idea what might cause local differences here.