In my opinion it's not only about India who just made a huge mistake, but I would say its a mistake for all those countries who banned crypto.
Crypto is a modern technology and those countries left it behind. Every country, civilizations should move ahead with the modern tech trends.
Blockchain is the technology while cryptocurrency is the product of the technology. Countries can choose to ignore existing crypto because features like decentralization, privacy e.t.c are somewhat a threat but can not ignore block chain itself,instead they can choose to develop on blockchain a more centralised product that favors them.
I love the tech because of its anonymity and decentralization. This is one of the best features of blockchain/crypto, whatever you say.
But I will prefer regulation over a complete ban. I know this is what majority doesn't want, but those "majority" should think deeply about the consequences.
So those countries who banned crypto completely could restrict, regulate or could find a solution instead of banning. They just didn't support this beautiful tech.
If crypto is not safe than what those governments think, fiat is safe?
Fiat is also being used to fund terrorists, money laundering, drugs and so many other illegal stuff. Then why governments can't control these illegal activities while fiat is complete centralized?