Any fiat contracts i.e futures/options/stock that trade on the cash value of the crypto has no relations to the supply and demand of the underlying crypto.
Currently the CME bitcoin futures is cash settled and ONLY tracks the PRICE based on a basket of exchange rates.
Once it starts. The investors in that product will have no price influence on Bitcoin so no need to worry about “short” sellers. If anything it will drive up the demand for bitcoin futures which might have a secondary effect and drive up demand on the underlying.