This misses a big point though. If Corporation A needs to pay $1M in crypto to Hacker B, Corporation A needs to acquire $1M in crypto (whether that's 20 BTC or 20,000). If it's illegal for them to acquire the crypto they can't make the payment. The bottom falls out.
Maybe. Let’s say you can, for example, purchase a cruise missile strike in crypto.
Once a few cruise missiles land in LA I imagine the world governments will take a more aggressive stance on crypto. Drone strikes and military intervention will follow.