Quoted from allsportdvd:
If the game designers thought that any other color than white was suitable for GI then wouldn’t they have put coloured condoms over the bulbs? That didn’t happen as the games were designed to have white GI so who are we to argue with the game designers? I believe there has to be a reason the original lighting wasn’t color bombed or am I missing something?
Actually, quite a few games did have coloured sleeves included with them. I wish there was a resource for identifying this exactly for placement.
For example, I know there were many yellow areas for Grand Prix (WMS), or at least I am assuming they were yellow.
Xenon originally (apparently) came with Red for near the back of the PF, and many Blue sleeves.
I think these sleeves muted the light more than anything, and I often find them with the original pinball manual envelope, presumably unused.
----------
That said, If the artist and designer had access to coloured LED tech, the games would probably resemble those of today, no doubt quite a lot brighter and colourful than incandescent white. the machine is after all, trying to get your attention. Using bright coloured lights is another way to achieve this, however not at the cost of blinding the user, or washing out all of the art etc.