> It seems that if we ultimately want to "move at the speed of thought," it will require speech.

Except for the large majority of people who read, type, and click way faster than they can talk. Especially for visual things it’s way faster to drag a rectangle than to describe what you want.

A lot of us also aren’t linear verbal thinkers. It would take minutes to hours to verbalize concepts we can grasp visually/schematically in seconds.

Great book on the topic: https://www.goodreads.com/book/show/60149558-visual-thinking

There's the adage that writing is thinking, but even more accurately at least for me, editing is thinking.

Neither typing speed nor dictation speed is a true bottleneck, but editing speech seems like it'd be harder than editing text.

Though there may be some hybrid approach that can work well.