The performance issue you talk about has a little more to it too. If the server is 30ms away from you and the other player, and the server runs at 30Hz there’s

The performance issue you talk about has a little more to it too. If the server is 30ms away from you and the other player, and the server runs at 30Hz there’s 90ms between the enemy pressing a key and you seeing it. That’s before you add real world networking conditions into the mix and have to start adding client side prediction in which adds a few more MS to boot, or errors. But in order to do this prediction the client needs a little more state than is visible on screen - players that are around corners that are about to appear, that sort of stuff. So the client needs that information in order to actually function meaning it’s hard/impossible to tell the difference between good game sense (I know the reload time of this gun is X and that peeking lasts Y frames and they will appear here) and cheating (we’re 2 frames away from showing the player on screen but he’s going to be right here so shoot here)