If it does get hacked, what incentive does the hacker have to make the hack public? Wouldn't the hacker want to keep it a secret so he alone could take advantage of a card that would likely have a  comparatively lower price since it would have no demand from miners?,(reply>), Yes, but also no. They could make money by selling the hack at black markets where the price would be insane. This would not hurt their personal profits as well if they stocked up gpus before selling the hack because their mining is independent of others. Also do remember that the way crypto's value work is by demand and speculation, if such a hack was released to make crypto seem more appealing, its price will go up and the miner would make even more money. Though yes there are a lot of counter-arguments, its just up to the hacker to decide which is more profitable