I'm not saying it's totally impossible to get rid of keyboards, but I feel this would require first significantly thinning down the amount of text that needs to be written, and the amount of abstract interactions with program that need to be done. The keyboard is very efficient in several criteria at the same time. Versus a 3D manipulation + verbal commands + weak AI, it's much more energy-efficient/ergonomic. Instead of waving your arms around in complex motions and talking a lot, you just have to move your fingers and wrists a little bit here and there. I know I can easily keep pounding at the keyboard for 8+ hours without much slowdown; I imagine that an interface of voice and direct manipulation would get one tired much quicker, if not mediated by another input device, or if the workload isn't reduced.

Now I was going to say that the trick is workload reduction, and that 'AI-glued boilerplate directed by voice' could just work by doing most of the task automatically, but then I realized: workload reduction doesn't work. As proved time and again in the last few centuries, as soon as you find yourself with extra free time due to some efficiency improvement, more work will be assigned to you to fill that time. You may not want it, your employer may not even want it, but someone over at a competing company thinks they can get ahead this way, and now everyone has to follow suit.