Some ways I could see the problem at least partially resolved on PC are: Returning to server-side validation, and designing games such that player location knowledge and aiming reflexes are not always the biggest tests for victory. Hackers may, in fact, develop wallhacks and aimhacks for such a game, but may exhibit frustration finding these alone don't necessarily bag them a win because of bad tactical decisionmaking.

Such games wouldn't be realistic tactical shooters in the vein of COD, though.