So you can make everyone else on the call suffer your horrible audio quality instead (room echo, etc.)? Probably not the smartest option when trying to get Management to get comfortable with work from home.
No you're confused - the point is it's better quality.
There's no limited bandwidth, and it's physically a larger microphone than the very limited micro one in your headset. It picks up the same background noise that its geometry can't eliminate, and can do the same processing to try to remove it.
Those are tiny microphones in your headset, and there's only two of them, sending back a mono signal! A MacBook Pro has an array of three much larger, higher-quality microphones, with high SNR and directional beamforming and the ability to do proper noise cancellation. They're also on a hardware bus to your system. The microphones in a headset just don't compete.
Try it yourself!