The wallet was completely illiquid. No market would accept coins that were linked to it. You could exchange small amounts(like thousands of dollars at most prob

The wallet was completely illiquid. No market would accept coins that were linked to it. You could exchange small amounts(like thousands of dollars at most probably) with in person transactions but then the government would know where you were when they track down the person you sold to. And they really want those billion dollars. Plus there's a non zero chance that the person on the other side of the in person transaction is law enforcement.