It is a solution on its own. Many cities have far more parking than they need - even on “black friday” there are empty parking spaces. Those parking spaces could be redeveloped to something else (not all of them as that something else will also need parking)

Of course the more you redevelop those empty parking spaces, the denser you get and the better chance is that public transit will work. The more people who arrive via transit the less parking spaces you need as well, which means more empty parking can de redeveloped.