Does your product need dark mode?

I recall reading an article about studies paper companies did in the early 20th century that found the same thing. (If the studies showed light ink on dark paper was easier to read, I'm sure businesses would have rushed to sell expensive patented dark papers and white inks.) Can't find references to those studies alas.

In the late 90s I inherited a SunOS workstation that booted with black text on a white background. (Could never get it working so gave it back.)