Shouldn't the goal be to create a bank ecosystem that is more robust? So that the failure of one does not lead to a domino reaction of failures?
You are seeing the robustness in the actions taken by the FDIC right now. Not all failure modes can be prevented ahead of time. There is no failure-proof banking system structure.
> So that the failure of one does not lead to a domino reaction of failures?
The "domino effect" in the context of bank runs is a result of human psychology, specifically herd panic behavior - not something that can be changed by the financial system. At best it can be tempered.