My long term bet: computing will move towards an interface driven by "emoji as command". Custom iconography will fade out as the interoperability (and familiarity) of popular unicode symbols becomes dominant. So much of the existing textual input we use is designed to overcome the limitations of our software. In the future if you want to go home then you'll ⌂. If you want to go to the supermarket then you'll U+1F6D2.…
In the 80s a pundit predicted that in the future the interface to spreadsheets would be a games controller, because that's what the kids were growing up with and would want to use when they grew up. Then 10 years ago it was txt shrt abrvs wr t ftr. Except actually they were just the product of now ridiculously dated numeric keypad input the kids of today know nothing about. The latest kids craze is always the wave of…
I'd say that the market have optimized creativly the gamepads to near 1:1 through put w/o having to think about backwards compatility.
What holds us back is the vast majority of minimum effort pencil pushers who want to spend 8 hours at work and don't care if things get done. They would never see the idea of making their job go faster say by a better keyboard and or by writing a nifty script to automate some dull toil. As long as they have a legally protected job they'll just go there 8 hours a day and don't care if they are doing something that could be automated in an hour!