It is not a solution to eliminate complexity. The electrical grid is an example as is the financial system. If we pave over New Mexico to generate green solar power, we need a complex electrical grid to deliver the power to the users, otherwise we all have to move to New Mexico. The power grid problem is a need for redundancy. Parts will always fail. We need to have enough redundant capacity to route the power around the failed component. The Internet is robust because it has lots of redundant switching capacity.
The financial system is a different animal. Its problem is not one of single point of failure, typical of physical systems, but one of systemic failure, algorithmic failure. It all breaks in the same way because everyone is using the same algorithm, whether it be everyone invests in real estate using the greater fool theory, or everyone uses the same risk management model, or everyone writes derivatives without enough reserve. The savings and loan crisis of the 80's wasnt the failure of a few big players, it was the failure of lots of local players. Back to engineering, these are failures of positive feedback loops. What is needed is negative feedback, something that pushes back in the opposite direction. In the case of derivatives, a reserve requirement is a negative feedback.
I think the financial system also needs the equivalent of the CDC to watch for viral memes. The South American loan defaults, the savings and loan crisis, the near failure of Lehman Brothers in the 80's all should have vaccine against over speculation among the financial community. It didnt. Instead we got Alan Greenspan.