Way too expensive to regulate in real time and the sample size for regulating is pretty low. What you need to do is make the punishment for bad behavior strong enough to minimize fraud. I would like to think most actors are good actors and we take the bad actors and make an example to the rest of the industry what to expect if caught. It will always be a cat and mouse game.

If the chance of getting caught is low, I'm not sure stronger penalties make that much difference. See the drug war for example.

General criminology finds that the certainty of punishment so long as it is non-neglible relative to the rewards is what matters more than the magnitude as most criminals don't think they will get caught unlike others.

It’s almost impossible to do that in real time. The problem is fraudulent activity can often be hidden behind a smokescreen of legitimate behavior, and stratigraphic investments can look overpriced. Apples acquisition of NeXt must have looked all kinds of shady at the time.