How can the price go down on a limited resource ? Eventually a shorter must buy BTC to pay back the BTC that he/she borrowed (that's how shorting works). But BTC is getting more rare every day.  In every dip on the markets, there is some farmer in zambia who bought his first bitcoin. Since there are a lot of farmers left in zambia without bitcoin, the transfer is still going from the few to the many, and no future contract can ever prevent that.