The issue with HSBC wasn't related to them not caring enough, what happened is that some employees in their Mexican office essentially went rogue. HSBC can't blackmail their staff, money launderers can. HSBC can't bribe their staff with suitcases full of cash, money launderers can. HSBC can't threaten to execute your kids, money launderers can.
And, again, even if you assume this all isn't true...banks do not have the investigatory powers. People who want to launder money do not turn up a bank with a briefcase full of cash, and wink repeatedly at the cashier when handing it over...they put substantial resources in disguising the source, and working out where the gaps are (with HSBC, it was currency exchange...this has been a weak spot for decades because it is mostly used by large corporates and there is an assumption that AML happens somewhere else in the chain). Police stopped doing this job because it was too difficult...and they had the powers, why people think banks can do it is beyond me.
The stuff you read online about low integrity or not caring is just obvious nonsense (it wasn't why police failed in the first place, police cared a lot, they just weren't as good as the money launderers so blamed banks).
Second rant part - regulatory compliance boils down to a "pain game" in so many old industries.. We know 'x-y-z' is happening but we shut it down when we find it, versus, 'newly promoted enforcement official needs to show success now' motivated audits, new regulations and 45-day decrees. All players at a certain size are guilty but the question is intent, awareness and effort to curtail.
Bluntly, the expression is "sh* rolls down hill" .. meaning that the least able, least aware and least mobile get stuck with additional restrictions, burdens, in some cases fines or entrapment, while Big Business shows up to work again tomorrow.