The population of India was actually pretty interested in the bitcoin, although not having a huge market share like that of some Asian countries like China or Japan. The regulation of RBI regulated entities by banks might affect a bit of the market share for now, but definitely will hurt BTC in the long term, due to decrease in mass adoption in the future.
The Prime Minister definitely did this move in order to support the Indian market, which was indeed lowering due to the crypto one, but also in part he did this to support the soon to be "Lakshmi", the bitcoin of Indian government, as they are calling it, although I doubt it would be successful.