That pays attention to the environment and changes the volume (part of the spectrum perhaps?) that is what you're likely to be listening to.

This is of course a huge oversimplification, and aiming for it is probably what the industry is doing.

That is exactly what the tech does, automatically adjusts based on the amount of noise and speech in the environment. And going a step further, applying directional microphone control to better pick up sounds where the speech is.