These are really solid concerns. This shift from "creator" to "supervisor" is happening in lots of AI areas - look even at how self-driving cars are currently expecting their human drivers to act as supervisors, which they're bad at.

Also, on this point:

> We can make proofreading easier with better tooling. Unit tests are a means of “proofreading”: we can catch AI errors automatically with tests.

The unit tests will definitely be written with AI as well. If that AI and the coding AI are wrong in the same way, we will have very subtle and hard to catch errors.