Even before the Colgan Air crash, it was widely understood that regional airlines' overworking and undertraining of their pilots was risky. But the regulators either weren't able to do anything about it in the face of industry opposition, or didn't care enough to do so. It took a plane actually crashing, 50 people dying and Congress, which was lobbied hard by the families of the victims, passing new legislation ordering them to do something about the problem to get them to take action.
It's great that we have regulations protecting passengers from these problems now. But it would have been much better if it hadn't taken the deaths of those 50 people to create an environment where it was possible for such regulations to be enacted. Good regulators protect people before there's blood on the floor, not after.