Attempting to obfuscate the origins and destinations of funds involved in criminal conspiracies by using cryptocurrencies is quite a terrible life choice.
Running a literal laundromat for purposes of laundering money is still a far more viable criminal enterprise than anything involving technology.
I suspect most of these ransomware operators have the support of some government which turns a blind eye in return for a cut. There's not much value in tracking the BTC payments back to the same damn Russian bank who never seems to have any "evidence of such activities".
Running a literal laundromat for purposes of laundering money is still a far more viable criminal enterprise than anything involving technology.