It's a fantastic use case. I could almost guarantee that anyone who disagrees hasn't lived under an oppressive government.
You can't pretend cryptocurrency is made to bypass only unjust laws and regulations.
There's a reason ransomware was not feasible with cash at the scale it's happening today.
All of those were done before cryptocurrency even existed. It's not enabling those things if those things are clearly possible without cryptocurrency.
Where there even cases of demanding payments for ransomware before Bitcoin?
Ransomware and international money laundering are easier with Bitcoin, Ethereum, and Monereo.
It's arguably their only real world use case due to the high overhead cost, risk, and instability of transacting though those systems versus "traditional" fiat based transfer systems.