I'm not sure I agree with the assertion "you can be confident that a compiler will express your program in the way you want". This is only if you program perfectly, which is never the case in practice (after all, bugs exist). What is different is how we can verify correctness (i.e. we read code to check correctness, but reading a text prompt carefully does not help if the LLM is sloppy). For code that is easy to test (i.e. passing a test suite convinces you that the code works, without even reading the code), I can see how the argument that LLMs are compilers makes sense.