Good. Then more people will choose different forms of transportation or internalize their costs. If parking becomes scarce, providing parking will become more profitable and people will pay the actual (enormous) cost of temporary car storage downtown.
Parking becoming difficult and/or expensive pushes patrons to places where that's not the case.
/s
And the 'spend' from people driving in from the suburbs to go shopping will easily be overshadowed by greater economic activity resulting from a denser urban core.
That's not really how it goes. This assumes that if you make it painful for people to do what you don't like (park), they'll stay and live the way you want.
But no, people will simply abandon the area due to inconvenience. The area I mentioned above (previous post) went from a nice affluent residential area to a dilapidated area where only the poor and university students (also poor) lived. Everyone who could afford to leave, left.
Humans will always look for a better solution for themselves unless you impose a complete dictatorship. It is not possible to advance a cause (whether it be less cars or more public transit or better EV support or better bike paths, etc) by simply making the status quo inconvenient. People will simply avoid it.
You advance a cause by making the new alternative actually more attractive, then the majority of people will happily adopt it.
This is the original tragedy of the commons though: a bunch of people assuming they can just park on the street. The frustration is the solution. Either build yourself private parking, pay for private parking, or ditch the car. Or enjoy the frustration.
The vast majority of people will choose "(D) None of the above". They'll move out, causing the neighborhood to decay.
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.
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.
This is what happens, and exactly what happened near here. All neighborhoods within a mile or so of the university require permits for street parking.
But here's the thing, fighting fire with fire does not lead to a nice society. Now it's a huge pain to visit any friends within that zone because they have to shuffle their cars (with resident permits) to the street so guests can park on their driveway to avoid being ticketed. When you fight fire with fire you also get burned. Lose-lose.
It didn't help that the urbanism activists in our area seem to consider parking garages to be a tool of the devil and protested any plans to build one in the area. To me they are an ideal compromise/stop-gap solution. They allow you to build dense walkable neighborhoods today even when most people will be driving. And once public transit has improved to the point where less parking is needed, you just have a few buildings to tear down instead of entire areas to redevelop.
Edit: And to be clear I think the "best practices" that most of the country used for the past 50 years to set parking minimums were massively inflated, and created many problems. I'm absolutely in favor of revising them, but I firmly reject swinging around to the other extreme of "to solve the public transit chicken-egg problem, we must make car use intolerable".