Once you get linux (or whatever) running on your embedded hardware (robot?) , you then spend some time getting all of the interrupts right and then compile your high level control language into C (and then compile that into the target MCU) and then... you emulate concurency via threading/tasks. If you go beyond C, you are probably running in a general purpose VM to boot.
For every lift of a mechanical leg, a megabyte or so of code abstraction, translation and OS task switching takes place. Ugh.
What is the alternative?
Very High Level Languages compiled directly to (or interpreted tightly within a simple VM upon) hardware with an inter-device messaging protocol. I want my Lisp/Oz/Haskell/Erlang/etc running on bare metal, baby! (And all programmed from within Emacs running on my laptop ;-)
Of course, Forth programmers already had this 20-30 years ago...