There is an easy fix here: make it illegal for companies to transact in crypt currencies. Then they would have no way of paying a ransom without engaging in illegal activities. This would destroy the ransomware business model.
It's like nobody has learned a thing from the war on drugs, my point being: you deal with the root cause of the disease (infosec in most companies and even government offices is a joke and bad people have taken notice), not playing whack-a-mole with the symptoms (crypto use) that hint towards systemic decay.
If the goal is to stop companies from paying ransom, then why not just make that illegal?
https://home.treasury.gov/policy-issues/financial-sanctions/...