Effectively, all cryptocurrency exchanges avoid transferring cryptocurrencies between customers. Instead, they simply record entries in a central database. This makes sense because actual “on chain” transactions can be particularly expensive for cryptocurrencies like bitcoin or Ethereum. If all speculators needed to actually receive their bitcoins, it would make clear that its value proposition as a currency simply doesn’t exist, as the already strained system would grind to a halt.
There is no single silver bullet to disrupt either cryptocurrencies or ransomware. But enough little disruptions, a “death of a thousand cuts” through new and existing regulation, should make bitcoin no longer usable for ransomware. And if there’s no safe way for a criminal to collect the ransom, their business model becomes no longer viable.
Note that these prices are for offensive uses of the exploit. Zerodium -- and others -- sell exploits to companies who make surveillance tools and cyber-weapons for governments. Many companies have bug bounty programs for those who want the exploit used for defensive purposes -- i.e., fixed -- but they pay orders of magnitude less. This is a problem.