The comparison of India to Africa isn't valid because the starting conditions are sufficiently different. Also note that the question is somewhat rhetorical. We de facto do have several kinds of citizen. Can you think of which kinds?
To provide a counter point the Ottoman Millet system seems to have worked pretty well at keeping the peace in that state. Also India is a bad example for your argument for another reason, recall some of the biggest problems the British had there was when they tried to abolish or weaken or even just ignore the traditional caste system.
Informal divides, including ones with consistent disparities of power and wealth, certainly exist everywhere. I'm arguing that it's not clear how government enforcement of them has much point. European countries like Poland or France enforced religious segregation too (Catholic and Orthodox, Catholic and Hugenot), and still had lots of strife along religious lines.
...Also India is a bad example for your argument for another reason, recall some of the biggest problems the British had there was when they tried to abolish or weaken or even just ignore the trad
As Multiheaded added, "Personal is Political" stuff like gender relations, etc also may belong here.