> Any non-determinism present with 0 temperature it's not some mysterious LLM-inherent property,

Of course it's not mysterious. It is well understood by all who are aware of the fundamental unreliability of all major LLMs in general use today.

The phrasing still makes it sound like it's due to the LLM. It's not. It's do to compiler and CPU, and OS optimizations, and a non-LLM program could suffer the same just as well.