https://www.dcpolicycenter.org/publications/discriminatory-housing-practices-in-the-district-a-brief-history/

I highly encourage you to read this. "The city turning toxic" is not the reason white residents left. Massive subsidies for suburban and segregated development (GI Bill, urban freeways, racial covenants) and resistance to desegregation in schools were the primary factors white residents left. The pattern of large sections of the tax base fleeing to the suburbs repeated itself all over which is why most American cities were faced with crippling budget shortfalls and racially motivated disinvestment in the 70s and 80s.