Due to the technical nature of bitcoin and the fact that most people don't even know how to work a VCR, it's a given the vast majority of the population will be using "bitcoin banks" like Coinbase or other entities and not taking delivery of their coins.  It will be even easier to short bitcoin into the ground than metals.  

Like I said, you don't even need naked shorts.  All you need to do is short the price below cost of production and force miners to turn off, which in turn further reduces the synthetic price floor through a feedback loop since cost of production is recursive based on it's own demand.  Anyone who doesn't acknowledge bitcoin is far more vulnerable to weaponized shorts than metals is either lying or doesn't know what they're talking about imo.

TLDR: there is no incentive whatsoever for the ESF to short metals below cost of production, but there's huge incentive for them to do so in bitcoin.