You don't need to look at the entire program at the assembly level to figure out parts that you want to optimise or prove for correctness. You do need to look at all the code the LLM generates in order to understand it.

You can learn to understand the patterns that compilers spit out and there are many tools out there to aid in that understanding. You can't learn to understand what an LLM spits out because by design it is non-deterministic and will vary in form and function for each pull of the lever.

You can learn to understand how high level concepts in code map down to assembly language and how compilers transform constructs in one language to another. You can't know that about LLMs because they generate non-deterministic output based on processing of huge low-precision tables.

It's not even a close comparison.