Sure but that means accepting the cost of having faulty modules running in production (and there is no guarantee that your LLM could fix a faulty module, perhaps it will just replace it with a module with different bugs. There's no way to know!)

This obviously won't fly for "serious" software such as airplane software, but I'm willing to guess that even customers of a low-stakes SaaS would get pissed off if your product regularly turns up new bugs.

I think it's easier to just do code reviews...

There are code reviews. At no point did I write no reviews, that's something you inferred.

Both me and LLMs are constantly auditing software.

In-fact auditing and QA is mainly what I do now and human audits become much easier when it's scoped to modules.