The thing is that you paid that debt once. The mappings are well defined and deterministic.

The whole purpose of an abstractions is to not have to look underneath it to make sure what you did with the abstraction is still correct. You can make sure because you, or someone you trust, did the work of paying that debt once.

With LLMs you always need to verify the output, for every generation you need to pay that debt. So it is not an abstraction.