First off, St. Louis isn't empty because of muh car centric infrastructure, it's empty because of deindustrialization. Secondly, parking lots are in fact a better use of space than empty, dilapidated office buildings.

Lots of buildings across the country have actually been torn down to become parking, I'm not an expert on St. Louis urban development but it seems like many buildings were torn down there and replaced with parking lots that make the area worse. Then there's fewer people, and the cycle of dilapidation and abandonment continues.

https://www.stlmag.com/history/looking-back-over-a-decade-at...

https://www.reddit.com/r/StLouis/comments/ipjho8/save_histor...