Everything is owned by members of the public. That is not a clever argument.
There’s no reason to be subsidizing this. It is not necessary nor helpful for the health of the city.
Not being geometrically sustainable means that a city with good planning doesn’t lean into it. It’s not the “result of poor planning”. You can’t change the laws of geometry with planning. Cars are an inefficient and ineffective transportation plan outside of the countryside and cities should only support them the bare minimum necessary while encouraging other forms as primary - subsidizing them by providing free/mandatory parking is leaps and bounds beyond the bare minimum and can quickly put to death sustainable urban growth.
When in the midst of a housing crisis we should not be devoting city resources to these intensely inefficient, regressive uses.