I've formally studied gamedev, but haven't done anything in over a decade, but even before you get to the thorny issue of anti-cheat sustems, games rely on running at a(n often very) low level and doing unconventional things. I imagine they're one of the hardest things there are to sandbox without causing massive levels of breakage. But someone more knowledgeable about either side of the equation (sandboxing and/or game development) might be able to shed more light.