They never were. It's all PR. That place has been one screw-up after another since J Edgar Hoover.
Before Hoover went.
At the end, he listened to the House Speaker from MA, and accepted a couple of Boston guys as agents.
They turned out to be pretty corrupt. The surviving one is serving time, just one of his many crimes, as an accessory to murder for providing info about a businessman that stopped the skim from a legitimate business he bought.
Decades later they/estates were awarded around $100M. The DOJ's been dragging paying them off, as I recall.