what does angle snapping do exactly?
Humans can't draw straight lines for extended movements so there is software to correct your movements by mitigating movements typically 5°-7° degrees depending on the engine as a straight line.
The implications in a gaming environment can depend and can have it's pros and cons. In particular to low sens when they turn it usually deviates a lot i.e. it's not as straight as say high sens due to the amount of distance needed to move the mouse especially in hectic situations. And even in some games it can be beneficial because it can keep your mouse cursor straight all the time thus having a consistent X/Y axis firing capability.
But that last one is also a negative because it's straightening out your movements. And I've even read of some people mentioning how angle snapping fights their control. And if your trying to aim at someone you might miss completely because the mouse is forced to go into a corrected path and not following your hand, wrist, or arm.
It really depends on the game not all games have negative consequences for using mouse prediction. In fact it's a nice feature to have a togglable mouse prediction depending on the user and the game they play. A great example is the MX518 despite the fact it's very popular even to this day, it certainly needs a complete reconstruction to improve on it(better material, microswitches, weight reduction etc.etc.) but it's engine has angle snapping despite the fact the engine is considered to be one of the best optical engines made unfortunately it might not be conducive to all gamers who don't like prediction.
