I don’t know how it is even going to achieve that…

It’s going to give you a code base that is filled with subtle bugs, no tests and no documentation. You won’t have a good understanding of your own product and you are going to almost certainly end up wasting more time over even a modest time window compared to the feeling of productivity you had at the start.

I feel like you could build reliable scaffolding tools with zero AI. Code generation tools are underused a lot of the time.

Correct and from there you can still build the tests and documentation to go with it and actually understand how everything works.

This is literally hoping that some linear algebra process is going to magically put all of the right things together in all the right ways while maintaining all of the correct syntax and the underlying logic will make sense. Sometimes I think people forget that it’s just a glorified guessing game of what letter most likely comes next.

It will only give you that codebase if that's what you ask it for. If you ask it for tests it will give you tests. If you ask it for documentation it will give you documentation.