Banks are just doing adjustments to fully integrate Blockchain Technology into their Banks, They are not scared, people -apparently- will always use fiat, they are scared that they might get involved in Shady crypto coins and Transactions. Banks are regulated while Crypto Currencies are atill in talks and process of finalizing their Regulation.
Ban? what is your reference for this?
Anyway, here's coindesk article related to Crypto Ban : https://www.coindesk.com/reserve-bank-of-india-denies- -in-draft-bill-to-ban-cryptocurrencies