I definitely did not know that lol. I wonder why they changed it. White= blonde visually makes more sense to me. But grey = red makes sense too. Hahapecs
It's actually pretty easy to tell blonde/silver apart from brown. While brown is solid white, blonde is usually white with extra shine (in black!) mainly at the crown and also along the lenghs
Actually for us veteran manga readers black hair is black, white hair is brown, and gray hair is red :)