We have minimum parking requirements that produce an oversupply of parking, therefore parking is cheap, therefore building parking garages is unprofitable. If you don't mandate them, the cost of parking will increase until building parking garages is profitable, and then people will build parking garages (or have fewer cars, in places where that's practical).
This doesn't even increase costs. Right now someone is paying $3000/month for a $2500 apartment and a $500 parking space. Without the parking requirements you could get a $2500 apartment for $2500 and choose whether you want to pay the extra $500 for the parking space.
Not only that, this would make it cheaper to build more apartments, so then the $2500 apartment drops to $2250 from lower scarcity, which reduces the cost of apartment+parking space as well by not force-allocating a parking space to someone who can do without a car and leaving more for the people who can't.
Bob wants to build it on the next lot over once he sees these new buildings going up and is willing to bet that the new residents will generate demand for parking, and can choose how many stories to make it based on the local demand for parking, which is based on numerous hyper-local conditions that are best evaluated by the owner of that specific lot and not just based on how many housing units are in each building.
Alice is a smart capitalist and will build two apartment buildings instead, maximizing profit from selling the units.
By the time the buildings are completed, the mortgages signed and the people start moving in and fighting for parking, Alice is long gone, moved on to the next project in some other city.
This is the problem parking minimums were intended to help reduce.
So Alice wants to build a high-density housing tower without having to build a ten-story parking structure beneath it, and we prohibit Alice from doing that, even though Bob wants to build a ten-story parking structure right next to it, because we prohibit Bob from doing that.
I feel like these could both be solved in the same way.