Yeah i think this whole miners stopping mining is irrelevant . If all the top miners stop mining then after a while the difficulty is going to drop back down and all the home miners are going to jump back on the bandwagon, When this happens your then going to get bigger miners mining again and then before we know it were back at full mining potential.
the miners aren't going anywhere. Someone will always mine it for the foreseeable future.
When you have Chinese mining farms getting cheap electricity from Hydroelectric dams built in the middle of nowhere, I do not think you will need to worry about the halving substantially causing the Bitcoin network to grind down to a crawl. Also, I am sure Bitmain has not shown us their full strength with the new S9 miners. Look for Antpool to become even more of a powerhouse soon after halving.