Lowering to $1000 needs a catastrophe I think. The hardfork being worse than expected or a very big exchange getting hacked. Other than that, I do not see it returning to that price again.
Catastrophic is small word for this to happen. Even if this segwit fail dont think it will be possible to go below 2000 think we have this price as lower price. For hacking dont think it will be that possible cuz dont have much on exchange, but exchange as global that can be possible but still hard. Think we are over with hacking for now.