That was my initial thought. But, it sort of defeats the point of projection mapping. The maps are being displayed on visually intricate, interesting pieces (think the Castle, Main Street Buildings, SSE, the carved Tree of Life, etc.). That way, they are interesting in the light, and the effect is how you are able to transform that visually interesting (and physically complex) surface into something totally different. If you do it on a flat or simple surface, it's just projection.Not sure if this has been suggested before in the course of these color updates, but is it out of the question that these new bright plain colored walls could be the canvas for continuous nighttime projection mapping throughout the whole land? Tree of Life has proven that something like this could be possible. Can you imagine what an amazing update that would be for the 50th anniversary?
If they wanted this, I would actually suggest the more streamlined white and blue palette would be the way to go - making the colors happen via projection.
Not saying that to flame or correct you at all! It was my reaction as well. It just seems a very odd choice given how odd it would look during the day just to support an effect at night.