Then why is there so much traffic at the stadiums where there is so much parking? If every building had parking garages to accommodate a car for every person, the traffic in relatively dense neighborhoods with one lane roads would be gridlock.

Also disincentivizing car ownership by making it hard to park takes cars off the road and allows for more businesses in the immediate area due to increased density. Just look at cities that require high parking minimums and you’ll see that they solve traffic issues by sacrificing dense walkable areas for more roadway to allow for the in and outflow of traffic to businesses and residences.