As an owner of Psion's 5mx and Revo (https://en.wikipedia.org/wiki/Psion_Series_5 and https://en.wikipedia.org/wiki/Psion_Revo), I've experienced the absolute minimum in a touch-typing keyboard. These machines offered, to me, the very best form-factor for a small computer (the clamshell design was ingenious). Sadly, nothing like these is currently available.

Conversely, a smartphone with bluetooth offers the flexibility of a touch-enabled computer with optional keyboard - one that's suitable for actual real typing!

So instead of an all-in-one solution, perhaps there's a case to be made for modular components too?