ok
lets straighten out the details
BANKS cant and wont get involved with something they cannot control.
so forget about banks getting in heavy with bitcoin.
BANKS will make their own chains and tether them to the IMF's hyperledger, to be inline with the laws that suppose to mitigate their risks by having control (yes having control can with bankers greed do the opposite, but they and governments wont let it be greed with no control at all)
PEOPLE eg citizens of india are not BANKS. people can choose to rmain holding fiat and be moved to the hyperledger project without knowledge of the change of how their fiat has changed. or they can choose to use bitcoin.
dont expect BANKS to get into bitcoin. but do expect PEOPLE to get into bitcoin.
Two ways it may go with bank-chains (really, without open sourcing & tokens to secure, isn't it just a shared database?)
1) They promote it as the new, faster, secure way to process payments. No more waiting 3 days internationally or a day domestically etc. In other words, some benefit but still in a walled garden (bank retain control).
This may become a trojan horse for the more nefarious option.
2) Blockchain & digital money, replacing cash. trapping account holders with negative interest rates. Rogoff has already mentioned that negative rates of -5% may be needed during next crisis. He is the policy head and leading non politician cheerleader of banning cash. "Blockchain" improvements may herd the masses in to a monetary Hotel california.
I don't think this will work long term - a massive scale rebranding of 'blockchain' will be needed as it is directly related to Bitcoin. I think any emergence of a blockchain system only feeds curiosity and increases bitcoin tourism. In the age of the internet and the current climate of zero trust in the mainstream, thats an uphill battle.