IF the whole world ban BTC at first BTC will Crash very hard but only for a few month, Demand will be increased while there will be no Legal Seller, All trade will go to undergrand and Black market and illegal traffic, sellers will start to selling BTC 50 X more than current price. BTC will be more expensive, As simple as that,
That was an answer for these who said BTC will die if whole world Ban it, So no BTC never Die.
There is picture in crypto market or whole world that BTC will banned forever. Besides this BTC price and demand increasing day by day. You can see in your country that how quickly it spreading men to men everyday. World now thinking blockchain technology and online payment system which is very easy and secure so that BTC will be more demand able day by day and no tension here.