I haven't owned a car for 15 years. Cars are useful and for some purposes necessary things, but in my daily life I really don't need one. I know I am smug about this, but I put so much value on not needing a car. How much would you have to pay me to go live somewhere I needed a car? That is a very big number. Very big.
And Philly, outside of a narrow bit, is not "Manhattan." It's mostly 2 and 3 story row houses. You don't need skyscrapers to have enough density for walkability.