This isn't about "geography" or "wealth". It's about infrastructure, urban planning and lifestyle. In the western world, the architecture of cities and regions has been redesigned during the 20th century to accommodate car use as the primary mode of transport. And it happen as a complex interplay between business interests, market demand and public governance, creating intricate feedback loops.
At the start of the 20th century, when the automobile was still in it's infancy, car use was looked down upon and there was even an anti-car sentiment.
e.g. https://www.vox.com/2015/1/15/7551873/jaywalking-history
It's worth paying attention to history and wonder how cars became so dominant a transportation mode in the first place.
In that regard, this statement:
> So, the biggest barrier is likely to remain the social will to rethink transportation.
Should have been the premise of the article. Not its conclusion.