I suppose those higher fidelity things are why it's so exhausting trying to voice-command a bot like Siri/Cortana/GA— at the end of the day, they're just doing a straight transcription into text, and then operating on that text.

So rather than the machine benefitting from that extra info, it's actually just making it worse by introducing another link in the telephone chain; hence users getting exasperated and giving up to go back to conventional HMI paradigms of keyboard/mouse/touch.