With mirrorless, the AF points could be any color, but with so many of them, the subject would not be viewable. They show them as white which is easy to see and they turn to green when in focus, but no more are all the AF points continuously displayed, and what is displayed is not the AF point, but a general area covering hundreds of AF points. 5,665 points is just not something I'd want to see in my viewfinder, and the new higher mp cameras may have a lot more.
With my EOS R, I tend to use a single or expanded AF point and it is continuously displayed in white, which works great for me.