For countries implementing a scheme of restricting use of private vehicles, there would certainly be an instant effect on reducing the traffic during peak hours.The congestion problem could be mitigated under the scheme. The advantage would include mitigating the traffic jam so that the highways will be less likely to be flooded by private cars. People will adopt new commuting methods, either through public transportation or on foot.
Since citizens are encouraged to change to more sustainable ways of transporting under such circumstances, cities applying these rules of restricting the use of private cars can minimize carbon emissions. Fewer emissions of carbon dioxide could effectively reduce the problem of air pollution, which could benefit citizens in the long run as the air pollutants drop drastically.
On the other hand, considering Hong Kong, cities with limited land resources suffered greatly since private cars also take up a lot of space. The parking lots are running under ridiculously high cost of rent. Minimizing the need of private vehicles would ease the burden of space shortage in Hong Kong. As more space is cleared for other usage, the problem of unreasonably expensive cost of land would be mitigated as well.
However, every measure has its shortcomings. Banning cars in specific areas might also affect workers in the logistics industry. The lorry drivers who earn a living through delivering goods around the countries should be exempted from the ban. Through deliberate modification, a scheme of banning private vehicles in busy area could maximize its benefits on both individual and society.