its just their way of trying to sell, and upsell, ugly/lower-quality stones.
Theres a reason brown diamonds are typically used for diamond dust/diamond-tipped tools. Its because its ugly.
I jokingly call them poop diamonds, because who would think a brown diamond is better than literally any other coloured diamond?
I had to explain to my mother-in-law the other day that they are garbage.
I don't know... While I agree with your sentiment, I still see a lot of women falling for the hype.