I sort of agree. Where I think you are incorrect is that race is extricable from the shift. When you had democrat leaders like Wallace and Thurmond (who coincidentally changed parties to Republican in 1964, when, what was it that happened then?) fighting segregation, it takes quite a reductionist view to think racism and the CRA was not at least holisitcally related.
Not saying it wasn’t a factor; I’m saying that it does not show up as a significant factor statistically. Wallace (who switched in 64, but then became an independent and then a Democrat again, since his economic views didn’t fit with the GOP) and Thurmond…..are just two men. Statistically, they were outliers.