My theory is that it very much has to do with pupil size/dilation. I have extremely large pupils according to my eye doctor, and it makes me very sensitive to light. For the longest time, all I saw was white and gold. When I looked again in my very dark room later at night it started turning to a periwinkle/brown. I was eventually able to get my eyes to see blue and black by squinting/tilting my laptop screen. In the morning with more light in the room, it was back to very light blue/gold.
This makes the most sense to me, more than anything I read, and seems like a pretty solid theory, but I could be wrong. Those who see B/B compare your pupil size to your spouse who see's W/G.
Let me know!