That fix was just never paid for, in terms of shrinking Fed balance sheets and renormalizing rates.
Additionally, if you don't address the lack of regulation that allowed the collapses in 2008, which we absolutely did not, it will keep happening and those future occurrences will grow in severity. Since now, in order to 'make money', the frauds have to be bigger, faster, and more aggressive.
What does that even mean?
Do you mean it in a philosophical sense similar to the idea that every company will eventually go bankrupt given enough time? Any major crisis is capable of bringing down banks, its inherently a feature of fractional reserve banking but the benefits have so far outweighed the risks.