I strongly believe that India is not doing correct here by blocking cryptos, messing with bank account of exchanges can break the trust of customers at the exchange, they will not buy there and some might even lodge complaint against exchange and indirectly expose themselves to Income tax department.
On the other hand if India makes a law to accept cryptos as a legal tender by linking with AADHAR card, they can monitor all purchases and a part of profit will go to government and companies will invest in India as they are pro-crypto.