I don't think it should be the responsibility of your device to make itself as close to useless as possible to deter theft. Besides, most thieves rarely do their due diligence on checking what phone maker or model it is, they just swipe it out of your pocket and sell it to the nearest pawnshop. Groups sophisticated enough to smuggle parts already do so with Apple's anti-repair measures. Besides, wouldn't such legislation force Apple to sell official new parts, removing the need to harvest them from existing phones?