The difference is that a violin player can predict how the known violin will behave under all relevant circumstances, will know how to get the right tone out of it, while you’re generally unable to predict the adequacy of output of even a deterministic LLM. You can’t practically reason about how varying the input to the LLM will ensure the adequacy of its output, while the violin player is perfectly able to do so for the violin.

This is because LLMs have aspects of chaotic dynamical systems, where small changes in initial conditions can lead to vastly different outcomes. That property is independent from nondeterminism.

Anyone who has even modest experience with a particular instrument can pick any one up at any time and play it. The way the notes are played is consistent and produces a consistent note. If you tune 50 guitars to standard, the chords all produce what they should., It is a predictable instrument. You do not pick up a trumpet in one place then another and find the key combinations are suddenly different.

You know what we are talking about. Tuning, poor playing, all of that is mild variation from what we know it is supposed to do every time and we can target the the notes they are supposed to hit consistently. You're comparing slight tonal variations to completely different outputs from the same inputs. If I hit a "C" on the piano, it is going to play "C." If it does not, then the piano is not functioning properly. LLM's for some reason get a pass on this and it makes them very distinct from musical instruments.

This feels like a very nitpicky steel man, not a productive attempt at discussion.