> Yet you wont find any of those subunits complaining about their central bank setting monetary policy.

This is ludicrously wrong of India, and I understand enough of human nature and economics that I’d be surprised if it were true of China, though it may be more suppressed.

Monetary policy is government policy. The ruling party is seldom uniformly popular across their entire domain. Perhaps you’re more familiar with US politics: broadly, rural is Republican, urban is Democrat. In India, the ruling party BJP has a lot of the north, but not so much of the south or east. Accordingly, you should expect dissent from regions with a different state government. And as for socioeconomic disparity between states, rich may complain if they seem to be subsidising poor, poor may complain if they don’t seem to be getting enough attention.