Compilers are deterministic, though. If you don't put garbage in, you won't get garbage out. With a probabilistic system you can have varying outputs for the same input, thus the need to spend (waste?) effort verifying that your output is quality.

No comment on the rest of your comment. The assembly piece just bothered me in particular.

There are still bugs in the compiler as well as in optimization that can be created. The only thing stopping bugs in production are unit tests. That's exactly the same as with AI-generated code as well.