You're also arguing a false dichotomy. (“Either taxpayers have to get smart, which they aren't, or we have to use regulators.”)
Getting screwed is part of any learning process, and lessons about individual cases can be encoded at large; I'm just arguing that regulatory bodies are one of the worst ways to do that.
I'd rather have 1,000 independent pen testers examine a bank[0] (and be compensated for it) than some operating manual–laden bureaucracy applying the same standard test every shark working at a bank knows how to side-step.
An infinite regress of regulation is a waste of human intellect and creativity.
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[0]: Imagine a bank in the style of an Open-Access Startup where the books and assets are laid bare, either to the public at large or their clients. This is no longer practically infeasible in the era of the crypto-ledgers but what engineer in their right mind would willingly enter the total regulation shitshow that is today's American banking industry? The best engineers have choice, so they go elsewhere.