One of the reasons the USAF uses blue-green filters on their cockpit lights.
The most likely, primary reason is NVG compatibility.
If you're used to red cockpit lights at night, the blue-green NVG lights take some getting used to. In some cases the rheostats may have to be replaced so the brightness can be adjusted better. Installing the NVG compatible light systems in all airplanes of a type would make the transition easier.