Don't agree with this at all.

On one hand, it's kind of a tautology - sure, if you're in a city that is very car-dependent, it's a disadvantage to the working poor because owning a car costs money.

But in the US there are also (usually older) cities with relatively great public transportation that are more walkable that also have enormous amounts of wealth inequality.

Doesn't really have anything to do with inequality, in the US at least it's mostly just reflective of when cities were built and developed. Pre-WWII cities like NYC and Boston have (again, relatively) great public transit options and huge walkable parts, while newer cities (often in the South) developed around the car.

Poor people can’t live in the places you’re describing so they’re going out of the public transit coverage

Wrong, there are poor people living in urban Boston and NYC and every city on the eastern seaboard.

The poor people living in Boston live in Roxbury and Dorchester. Coincidentally, these are the areas with by far the worst car dependency and worst public transit in the city.

I've worked extensively with impoverished Cape Verdean populations in specifically those neighborhoods and lots if not most do not have a car.

Apologies, I was basing my take there on having biked through most neighborhoods and witnessing the worst traffic by far in those areas, so it certainly feels as though the car density is the highest. (It's also the only place I've ever been hit on a bicycle, and then had someone behind me get mad for being in the way while I was picking myself back up)

That sounds awful. Impoverished areas are well known for lacking traffic calming measures leading to higher pedestrian and bike accident, this is certainly true in my home city of DC.

On the flip side, Boston is the only city where I've ever hit a car with my bike.

Lack of adequate transportation has been cited as the biggest barrier to upward economic mobility

https://www.nytimes.com/2015/05/07/upshot/transportation-eme...

That certainly makes sense, and I agree, but I interpreted the parent comment ("our urban conditions are primarily reflective of the vastly unequal socio-economic structure we have at large" and "In places where the working poor are the most disadvantaged, there also tends to be the highest auto dependency") as inequality being a cause of our poor transportation infrastructure, instead of our poor transportation infrastructure making inequality worse.

I agree that I perhaps poorly framed my comment earlier. By reflective, I think I was really thinking of a cyclical relationship. Where lack of transportation compounds inequality, I also believe that inequality is at the very least, co cyclical with poor infrastructure due to a lower interest in collective investment in that infrastructure and greater private control in development.

An example of such would be Atlanta, where public transit investments have been sparse due to wealthier areas of the metro having little interest in funding transit. Many wealthier residents live suburban developments that are highly car dependent. As the article points with walking, many wealthier areas opt to avoid transit access, many residential areas do without sidewalks and follow a land use pattern that (effectively) cuts the neighborhood off from pedestrian access

The problem is that the shining example of low-inequality urbanism (Western Europe) achieved this by having effectively the most exclusionary immigration policy in the West for two centuries.

Europe may have great biking culture and equality, but they have effectively sacrificed pluralism.

This is a very interesting angle on a trade off that I (as an American) have not considered and be interested to read about.