Muti-generation photocopies tend toward black and white only.
And not just for printers and e-ink. In most parts of the world, 6-10% of population have some degree of color blindness: https://en.wikipedia.org/wiki/Color_blindness#Epidemiology
I’m not one of them but that’s huge count of people. Ideally, interfaces/visualizations need to be designed accordingly.
There are lots of parameters which can be varied to choose which colour range to cover.
I've seen graphics and charts that looked fine on monitor become almost unreadable when projected, projectors tend to be lower resolution then monitors and color scale is not always the same.