How do you prove that X was negligent? It would require some auditability, as well as review by a human expert to make a determination. If we have that, then we didn't need to leave regime 1, because the AI can explain itself in a way that a human expert is able to understand (ie human can model the behavior). If we are keeping AI accountable to human laws, then we have to be able to model their actions and judge them. And it is highly desirable that we keep AI accountable to human laws.

The regulatory approach will always be too high cost and too low coverage to give useful guarantees, unless the tools are very narrowly scoped.