But it really jumped out at me, so I decided to bring up the topic for discussion. Here's what I noticed:
Many of the stories with white heroines feature a prominent rescue and/or capture fantasy narrative. Regardless of how physically strong or intelligent the heroine, the hero captures and/or rescues her at some point in the story (sometimes more than once). The heroine occasionally contributes to the mission (many of the books in question have an external plot), but the role of savior is consistently assigned to the hero.
Based on the same sample, books with a PoC heroine feature a different type of fantasy narrative. It involves the heroines either doing the rescuing/protecting, or playing an equal role with the hero in saving the day/defeating the villain. And the capture fantasy is noticeably absent.
The sample of books I've read could be an anomaly, but on the other hand, the pattern emerged at a time when more SFRs with PoC heroines have become available/visible to me.
The sample is small and completely unscientific (and therefore your reading sample may yield different results), but felt significant enough that I wanted to analyze the pattern. Why did part of the core fantasy strike me as markedly different, and why did it seem split along racial lines?