>Specifically, film in general was strongly biased to favour Caucasian skin tones
I find it odd to call this "biased". It's about physics: due to light intensity, it will be generally easier to photograph (capture on film or digital sensors) objects that reflect moderate amounts of light with some contrast, than objects that reflect very little light with little contrast.
> Yes, film wasn't sensitive enough for black skin
This was not a constraint of physics or chemistry: Kodak knew it, and they didn't care much for black skin. This was bias because they could fix it, but didn't. Fortunately, Kodak did ended up caring for other brown things: Kathy Connor, an executive at Kodak, told Roth the company didn’t develop a better film for rendering different gradations of brown until economic pressure came from a very different source: Kodak’s professional accounts. Two of their biggest clients were chocolate confectioners, who were dissatisfied with the film’s ability to render the difference between chocolates of different darknesses. “Also,” Connor says, “furniture manufacturers were complaining that stains and wood grains in their advertisement photos were not true to life.”
I find it odd to call this "biased". It's about physics: due to light intensity, it will be generally easier to photograph (capture on film or digital sensors) objects that reflect moderate amounts of light with some contrast, than objects that reflect very little light with little contrast.