This is the reason why we should use blockchain technologies with KYCs to prevent such things from happening. Banking systems are almost obsolete and corruptable in itself so we must implemented new systems to make it s deterrent for people to launder money or even fund terrorism.
At this scale of money laundering KYC doesn't achieve anything as the culprits are able to simply buy their way around it.
At its fundamental cryptocurrencies are free of KYC / AML while most banks had to implement such a procedure since more than a decade. Yet the brunt of money laundering still takes place using banks. Go figure. KYC / AML is only effective to catch small fish like common darknet merchants, not the real whales.
Why do banks have to wash money? Is it to escape government or international taxes? This kind of news is amazing. They took full advantage of the shortcomings of Bitcoin. Perhaps this is a way for them to oppose Bitcoin, but I believe they will fail if they don't work with cryptocurrencies.
When banks are involved in money laundering schemes it's usually for customers, not themselves. Some people have a lot of money to move that comes from questionable sources, as such there's a demand for such services which some banks happily provide. As audaciousbeing pointed out it boils down to banks being in full control of the capital and its movement and money laundering being a lucrative business; mixed with limited legal consequences. Put together its too tempting a situation for some.