Sorry, I don't buy the premise.

The future of UI (for the general public) is probably voice-based like "Hey Siri/Google/etc, I'd like a sandwich" and a sandwich is ordered and delivered to you. "Tweet 'Who's down for a sandwich party?'" and a tweet is tweeted.

Whenever I hear or read someone argue that "command line is the future" I think of my dad; barely able to make a bookmark in a browser and not really knowing how folders work. And he's been using a Mac for decades.