Comment by gowld
Modern connotations of the word "miscegenation aside" aside (the word's denotation means "mixing of races", which is exactly the correct terminology for the issue), and laying aside modern understanding of "race" vs "ethnicity", in Fisher's era racial separatism was considered a solution to racism, not only by White people but also by many leading Black rights activists, such as Malcom X and Muhammad Ali in the Nation of Islam. Ethnonationalism may well be a bad idea in theory or or practice, but it's not purely an oppressor's idea. (It's not obvious that there is any unalloyed good solution to racism and human nature.)
https://ccnmtl.columbia.edu/projects/mmt/mxp/speeches/mxt14....
https://www.npr.org/sections/codeswitch/2016/06/10/481414008...
It was common enough at the time to hold the opinion that "mixing of the races" resulted in offspring that were worse than either race.
Frequently expressed across the colonial Commonwealth, Canada to Australia, South Africa and elsewhere.
eg Daisy Bates (sometime wife of Breaker Morant) wrote in the state newspaper in regard of Australian Aborigines:
~ https://en.wikipedia.org/wiki/Daisy_Bates_(author)Miscegenation Laws regarding mixing of races remained in force in Bates part of the world until the 1960s, as did others enforcing the separation of mixed children from their families.
It seems less "a solution to racism" and more an excuse to enforce racist ideas aand attitudes.