1)the synchronization requires a lot of infrastructure the influx of traffic leads to high pollution and crowd in the city. No matter how smart the city is the crowd and traffic prevails. Even in Berlin an Paris sometimes it becomes tough to control traffic which leads to jam. Those are less populated countries.
2) The geography of India is different from Europe and Japan and has different climate and high pollution. So if you build a sky scraper it will start looking dull after one year, similarly the signals and overhead flyovers will look muddy due to winds from Thar desert in North India. And humid climate in the peninsular religion. The Smart will become ugly in just 12 months even if maintenance is 24/7. I have seen that in Delhi Metro. The color has totally changed. Looks muddy and kind of old.
Green cities are best suited in India because of the climate. Green cities promise, low pollution, more over the climate will have no effect on the buildings due to the greenery around the infrastructure. It makes sure that it look smart and green through out the year. You can add all the infrastructure, like hotspots, monorail , etc but it should look good also.
Traffic still remains the problem, and that is not due to the roads are not wide enough but there is no proper lane system followed by we Indians.