In reality, when a short covers they buy back the stock and pay back the broker or market maker they borrowed it from. Then the broker or market maker sells it again. Then the short can buy back the same share, over and over again, as long as they can find someone to sell it to them. That "as long as they can find someone to sell it to them" is what's going on here - if everybody HODLs, the stock doesn't circulate, and the shorts have to pay increasing amounts to incentivize other weak hands to sell. But total short interest > 100% doesn't mean anything other than that there are a lot of shorts whose need to cover might blunt some price declines. Unless those particular shorts are right up against their margin limits, they can just hold the short position open until WSB loses interest.