If using a taxi becomes cheap and convenient, the need to own a car goes down.

I don't use a car near enough to justify owning one, but have considered getting one just because taxis are unaffordable for any bigger trips and carsharing can be a pain in the ass (mostly having to get to/from the carsharing station, inspecting for damages, and the lack of flexibility).

Solve those problems, and I will actively not want to own. Parking is expensive.