Many forms of cheating revolve around modding the game locally so that certain textures can be seen through walls, so you always know where opponents are. So you aren't breaking any laws of physics, you are just able to make much better tactical decisions.
The obvious solution would be, just don't send data to the player's client about enemies that are behind walls. But this is a surprisingly hard thing to engineer in realtime games without breaking the player experience (see: https://technology.riotgames.com/news/demolishing-wallhacks-..., and then notice that even in the final video wallhacks are still possible, they're just more delayed).
The obvious solution would be, just don't send data to the player's client about enemies that are behind walls. But this is a surprisingly hard thing to engineer in realtime games without breaking the player experience (see: https://technology.riotgames.com/news/demolishing-wallhacks-..., and then notice that even in the final video wallhacks are still possible, they're just more delayed).