Lol, Im not expecting that to happen, cause if it does happen, it will make a lot of miners to drop out and stop their mining. They wouldnt be profiting from it and there wouldnt be much miners left, so that might make the difficulty to increase. Although someone here said something good about it he said it will make it possible for people to be able to mine Bitcoin with their laptops, although I dont know if thats true.
when all miner go out , no more bitcoin trascation confirmed and finally failed.with less miner, bitcoin transaction speed could be slower.and make people think this is not suitable anymore to replace fiat.