Compare the actual operations done for code to add 10 8-digit numbers to an LLM on the same task. Heck, I'll even say, forget the possibility the LLM may be wrong. Just compare the computational resources deployed. How many FLOPS for the code-based addition? How many for the LLM? That's a worst-case scenario in some ways but it also gives you a good sense of what is going on.
Humans may stop looking at it but it's not going anywhere.