Least expensive countries to mine Bitcoin
Venezuela — $531
Trinidad and Tobago — $1,190
Uzbekistan — $1,788
Ukraine — $1,852
Myanmar — $1,983

The price to mine BTC in USA in 2018 is $4,758

http://fortune.com/2018/03/07/bitcoin-mining-costs-global-south-korea-venezuela/

So the potential for BTC price to drop into the $4K range is not going to be limited by the costs of mining.

Also, consider that with Soros entering the BTC market place, he is most well known for making lots of money for SHORTING.

So Soros can makes lots of money by shorting, and if you are going short the most money to be made is by shorting BTC all the way down to $0.

Remember the BTC futures market do NOT settle with real BTC.

So if you NOT settling with real BTC, then the futures price for BTC can go to $0; Soros can make a few more billions, and crash the crypto market down to nothing