The selection of the TV's input is a TV function.
The Roku has a CEC function (Roku name "1 touch control") which permits a CEC-equipped TV to switch to the Roku's input when a Roku key is pressed.
If the cable system fails to provide a similar function, that is hardly a shortcoming of the Roku.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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