Well, for a long time, lots of people. Including scholars. Particularly black scholars.
If sex was once difficult to discuss openly, black sex was especially fraught. It touched on too many taboos: stereotypes and caricatures of "black Hottentots" with freakish feminine proportions; of asexual mammies or lascivious Jezebels; of hypersexual black men lusting after white women. It brought up painful memories of white control over black bodies during slavery; of rape and lynching; of Emmett Till, a teenager tortured and murdered in 1955 for supposedly flirting with a white woman