I think you are definitely right that classism could also produce the same effects! However, in the US most of our classism is motivated from racism, I think. Or perhaps, if we didn't have the racism, we'd still find reason to be classist. Here is the current US president being explicit about what is usually the quiet part of the Southern strategy:
> The Suburban Housewives of America must read this article. Biden will destroy your neighborhood and your American Dream. I will preserve it, and make it even better!
Fear-momgering about blacks being able to move into your neighborhood, like what's happening in this Tweet, is what shaped the single-use suburban dream. Levittowns, the first cookie-cutter suburbs lacking any sort of small commercial businesses, were very explicitly segregationist.
It may be possible to disentangle the racism from the classism, but in the specific example from the US, they are so tight that I have a lot of difficulty being able to find any space between them.
I don't think you need racism or classism to describe the behaviours that lead to neighbourhood shops disappearing from suburbs, or not being planned for in the first place, though examples exist where those things are intertwined like you've illustrated.
What I don't see is the causal link. This phenomenon occurs in other places in the world, places that don't have the same interweaving of racial issues throughout society that the USA has, and it doesn't occur in some locations within the USA that does have those same issues.
It may be true that all suburbs in the USA were founded for racist reasons, or that the residents make all decisions about perceived house value and their community based on racist ideals, or that city planning policies are put in place to fulfil racist agendas, however;
It seems far more likely that the underlying causes are driven, like the rest of the world, by
- rational individual economic decisions, and
- policy informed by lobbyists
Now the effect of these decisions or policies may well be racist or classist - like I said above, people with money tend to have more agency, and it's definitely true that the USA has had and continues to have significant divides in wealth between various racial groups.
There are also examples of specific, explicit racism that have caused this effect, but those pale next to the impact that the widespread adoption of the car (and many other things!) had on decision making.
These decisions changed the way our world works, the true impact of them took decades to register, and we are only now adjusting for what we have learned. There are racial and classist components to these impacts, but that doesn't mean the decisions were (on the whole) motivated by race or class.
> The Suburban Housewives of America must read this article. Biden will destroy your neighborhood and your American Dream. I will preserve it, and make it even better!
https://twitter.com/realdonaldtrump/status/12863721751177912...
Fear-momgering about blacks being able to move into your neighborhood, like what's happening in this Tweet, is what shaped the single-use suburban dream. Levittowns, the first cookie-cutter suburbs lacking any sort of small commercial businesses, were very explicitly segregationist.
It may be possible to disentangle the racism from the classism, but in the specific example from the US, they are so tight that I have a lot of difficulty being able to find any space between them.