There's definitely a core set of drivers who can't give up their cars, for whom any price increase will just be swallowed. However there's a big swath of gray cases at the boundary.
For example, when we moved to San Francisco, we kept our car and parked on the street. After two parking tickets within the first month (because we forgot the weekly sweep schedule), we decided it didn't make sense to keep the car. We sold it, and started using Caltrain/Muni/biking for most of our trips, with a few Zipcar rentals peppered in. Without those parking tickets, we would definitely have kept our car because there would be no downside.