If you think your compiler will respect your code's semantics, you might be in for a rude awakening.
And there are certainly ways of influencing an LLM to be "more deterministic".
So the statement not only makes sense, it is fully inclusive of your claimed boundary condition of "completely vs. not at all". Last I checked, "not at all deterministic" is, in fact, "far less deterministic" than "completely deterministic".
YMMV.
¯\_(ツ)_/¯