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 traditional caste system.

And still their rule eroded it in practice - and who would mourn it? And OK, why not look at British colonies compared to French and Dutch ones and try to see what policies correlated with less blow-ups.