A company going bankrupt does not mean any decision makers were negatively influenced enough to not repeat the actions. I doubt THEY went bankrupt.

I don't know enough to say if your conclusion is true or false, but I dont follow your logic. Why can't bad actors, if they are pervasive, cause a systemic collapse? From what I heard, incomes were fabricated, risks downplayed, and policies ignored. The insurance against the risk was priced on false premises. How can these bad acts (by bad actors) not cause a risk of systemic collapse?