If that were the case, then de facto segregation wouldn't be increasing even to this day. Without the government enforcing segregation, people started separating themselves physically. Schools for instance are more segregated than they were in 1975.
Segregation wasn't a case of the government pushing these ideas on to unwilling populace.
This could actually be because of forced busing of whites to black schools.
Many parents want to send their kid to the best school and were willing to move to avoid their kids going to worse schools.
White parents were more likely to be able to afford to move which resulted in them leaving. Minorities tended to be poorer and could not leave and stayed in the areas with the worse schools. Kids who go to worse schools are less likely to get out of poverty so they stayed in the same poor areas and had kids in the same area repeating the cycle.
Since schools are typically given money based on property tax it meant that the schools in poor areas tended to receive less funding. There are also issues with teachers getting lower pay if they were in a poorer school. I think these issues are fixed in some states but there are still issues related to this in various states.
Segregation wasn't a case of the government pushing these ideas on to unwilling populace.