Wouldn't these be good examples? Boston is a pre-car city that weathered population decline well. Detroit was a city that rebuilt itself around the car and experienced decline.
Boston/Cambridge long had a major research university base as well as a fair bit of industry especially in East Cambridge and what's now the Seaport area. Also a significant financial/legal/etc. district. A lot of the industry did have significant declines maybe a couple of times in the 20th century. East Cambridge was really only revitalized in a major way when Pharma/biotech came in during the 80s/90s--and the Seaport redevelopment is ongoing.
There certainly have been efforts in Detroit and apparently the riverfront gentrification has progressed considerably but the city as a whole still is in generally poor shape and for a variety of reasons is probably less attractive overall than coastal cities are.
ADDED: And Boston may be a "pre-car city" and does have a decent public transit system but most adults still own cars because a lot of their friends and activities will be outside the city.