Opus works great for speech recognition but I wanted to point out how your argument doesn't support the conclusion logically.
Lets imagine that human speech had a nearly unique property of having another whole copy of the speech in the form of ultrasonic overtones at 10x the normal frequency at a loud volume.
You couldn't hear them and yet you hear speech fine. But a computer could make good use of the ultrasound portion-- and maybe understand speech much better than you as a result.
This isn't how it works in reality, but it does show a flaw in your logic.