Do you hide the cables?
Yes, on every job. Where the wall is hollow and the run is legal we put the cables inside it. Where it is solid, or where the power has to stay accessible, we use paintable trunking instead. We will tell you which one your wall is before we start.
Cable management is part of every install, not an extra. Where the wall is hollow and the run is legal, the signal cables go inside the cavity between two low voltage plates, one behind the screen and one behind the media unit, so nothing is visible between them.
Mains power is treated differently. A flexible appliance lead is not rated to sit inside a wall, so hiding the power properly means an outlet fitted behind the screen rather than a cable pushed through a hole.
On solid walls, and anywhere the board cannot be opened, we use paintable trunking instead. It is shallow, it takes emulsion, and from the sofa it disappears. You are told which of the two your wall needs before anything begins.