I don't understand what this accomplishes? Monitors produce their own light, with the brightness being adjustable. Including local dimming zones or per-pixel zones in OLEDs.

The only benefit I can see is if you cannot touch type and need to see your hands, but isn't key lighting the normal solution to that problem?

PS - I used to work with someone that needed the overhead light on to see their LCD monitor better. I'm still confused by that to this day.