It is unfortunate that more than 50% of Indians are so poor they don't even have bank accounts (IIRC), and, for them, there can hardly be a worse calamity than the banning of cash transactions, or at least the 500 and 1000 rupee notes.

There seems to be very few and slim vectors for the unbanked to migrate to cryptocurrency.

Steemit might be the one, nominal vector for adoption of crypto in such a situation.