They hate crypto currencies because of their own selfish reasons. They fear that usage of crypto currencies can replace them. Crypto currencies are decentralized, this means that no third party needs to be involved during transactions which is what banks actually do.
I believe bankers' opinion is not at all matter for bitcoin as it is anyhow going to replace them. It may take some time but definitely it is going to happen. Because, people from around the world start realizing the importance of having decentralized system for their financial need. Banks are actually devaluing common people's hard work whereas a deflated system increasing the value of people's savings . This core differences will be the key. Yes, that is the real success of of being decentralized with limited supply.
If cryptocurrencies prevail and fiat comes to an end, then banks will also come to an end. If banks come to an end, the people operating the banks will end up being jobless.
No, that will not happen in a single day hence people will be having enough time to switch over to new jobs. Moreover, blockchain based systems will be innovating and creating lots of new jobs hence the questions of unemployment due to this is completely meaningless.