The second reason for people leaving cities was because of a sharp increase in crime, especially violent crime. The political leaning of the 1960's and 1970's were to be very soft on crime and that era is marked by a stark rise in crime. People that can afford it will not live in a high crime area - go figure! They move to an area that is nicer and the politics of those areas tend to be protective in that they don't want the same political policy that allowed crime to soar.
This of course starts a chain reaction where there are better living conditions and lower crime outside the city and the city begins to rapidly lose its tax base. The entrenched politicians are more concerned with having power than managing a city and the city rots. So they scapegoat people for being "racist: because they didn't want to live in a crime infested, cramped, hellhole when there were viable alternatives. The market speaks.
The main reason people left cities was because of better living conditions in suburbs and the rising tide of high crime in cities. That's it.
regardless, your suburb vs city dichotomy ignores the great migration from the south. rural folks in the south moved to urban areas in the north. it's not suburb vs city. it's rural vs urban. my criticism of this study is about that, it used an example of a city where there's been growth and urban sprawl in the metro area as a whole, but ignored that and only focused on the city of jackson itself. jackson has lost a lot of population for various reasons, but seeing that example in this article about the study set off a critical flag in my brain. it seems like a simplistic look at jackson without examining the metro area as a whole. it might do that and i just didn't read the study.
Racism played a part too of course but class is often completely ignored in the USA.
See also block busting.
Many properties in areas that were claimed to be "block busted" by revisionists were of low build quality to begin with were aging out and were unlikely to be revitalized by whoever lived there in the future. As I mentioned, because of the depression and WW2 there were not many new things being built and the existing stock in many of these areas was already low quality to begin with and had gone decades without much investment. Therefore the demand was low for these properties and lower class people were the market for them. So the neighborhood began to change and more crime was brought into these places which only accelerated the plummeting of values.
People act like an area of affluent people living in high quality homes all ran for the hills as soon as a black family moved in and the prices plummeted. No, it was places like the south side of Chicago which were always working class and full of small, cramped living places. Building huge housing project towers in these areas didn't help either, nor did the highway systems that cut through these areas. But people got out because the living conditions sucked compared to what was available in the new suburbs being built. Not to mentioned, jobs were moving out of cities because business could expand to new locations that were safer and not cramped.
Did race play role? Sure. As did class to a greater extent. But the narrative you hear and accepted as fact just doesn't reflect the total reality.
The first person to integrate that neighborhood was a banking magnate. They bombed his house. Five times. They bombed banks and real estate agents who sold or lent to blacks.
Racial covenants were popularized as the more progressive way to keep neighborhoods segregated because racial violence was so bad.