now it's way easier to track public blockchain transaction chains on Bitcoin, Ethereum and the like than it is to track bank transfers across countries
Sure but you skip across borders, use mixers, over the counter trades and dodgy offshore exchanges.
It’s not that hard to cover your tracks. And sometimes it doesn’t matter if your beyond the reach of the authorities in the country the crimes were committed.
now it's way easier to track public blockchain transaction chains on Bitcoin, Ethereum and the like than it is to track bank transfers across countries