Color-blindness considerations for Designers and Content Managers by Sheri Byrne-Haber on Medium lays it down starkly:
It is completely unclear to me why designers think that it is acceptable to use colors (or combinations of colors) that others can’t see. This is a wide-spread problem that is very easily avoidable. The designers, who generally have unimpaired vision, think their color choices “look good.” However, if people who are color blind or older can’t see them, they are discriminatory. It’s also a ridiculously bad business practice?—?the whole purpose of thoughtful design is to ATTRACT users to your website / app over that of your competitors, not drive them away.
I also learned from this article that a sizable proportion of the populations (mostly older people) cannot see pastel colors.
Christine Kelley of Dreams of Orgonon has gone and made a deal with God by coming out as trans and this is as good a time as any to mention that Dreams of Orgonon is really good.