Indoors I tend to cast some show or youtube video. Often enough I want to change the Youtube video or show using voice commands - I can do this for Youtube, but results are horrible unless I know exactly which video I want to watch. For other services it's largely not possible at all
In a perfect world Google would provide superb APIs for these integrations and all app providers would integrate it and keep it up to date. But if we can bypass that and get good results across the board - I would find it very valuable
I understand this is a very specific scenario. But one I would be excited about nonetheless