Fretless string instruments like the cello and the violin are notoriously hard to even get a good note out of. Beginners just learning to play tend to produce a

Fretless string instruments like the cello and the violin are notoriously hard to even get a good note out of. Beginners just learning to play tend to produce a sound not unlike a cat being strangled. Playing a cello takes real skill. Even producing a single good note takes practice. Whereas on a piano, producing a good note is trivial. The skill comes in playing a complex requiring 10 fingers. So I guess the author of the article expected these new AI systems to be more like a piano, but ue got a cello instead.