The paper doesn't say that higher audio makes people sound smarter. It basically says that it high fidelity audio makes smart people sound smarter than they do

The paper doesn't say that higher audio makes people sound smarter. It basically says that it high fidelity audio makes smart people sound smarter than they do with low fidelity audio. It's quite possible that it just allows people digest content better or perceive more subtle nuances and that high fidelity audio would make dumb people sound dumber than low fidelity audio.