Jeff Bezos wanted this (though unsure if it was his idea) for the original Amazon Echo. The "mute" button was originally transparent, revealing the circuitry of the switch, enabling users to visually verify that the circuitry of the button severed the microphone in order to power the red mute LED.

I don't think it's that nobody _likes_ the idea, I think the problem is that very few people really care. You see this in products everywhere. Rough edges sacrificing the user experience which could be technically solved but are punted in favor of More Important Things.