The banks are only looking at payment network systems, not proper cryptocurrencies. They are at best proof of stake based systems but they are also permissioned - the transactions are not going to be irreversible nor are they going to be visible to the public... Quite simply, their payment systems suck, and cryptos are in the process of displacing them from the long distance money transfer business, and even short distance, after a 4 day wait for a Netherlands to Netherlands transfer, and wondering if this was 'Evropeyski standart'... The UK has instant interbank payments, and within Bulgaria and between Bulgaria and Australia I saw transfers go through in under a day...

I think the issue is that payment speed is such a big issue for them and they have been trying to stop people having this for a very long time, except through their mastercard and visa systems, and now even people without a bank account can send money instantly across the world (dash, steem, etc). They are so far behind the curve that it's quite laughable to suggest that they could 'kill bitcoin'. Probably bitcoin won't even die if the bitcoin foundation imploded, the chinese would keep running the network, at least, and take over development.

What might kill bitcoin is one or several of the newer cryptos that actually solve the problems that nearly no other crypto solved. Fast transfers, smart but secure smart contracts, etc...