Dangerous type of stuff.
Bitcoins aren't that dangerous but dealing with other peoples money is something that you shouldn't want to do unless you have experience or you have the money to backup whatever it is that you'll lose.
Bitcoins were built so that nobody could runaway with the money when banks collapse, when someone talks about making a Bitcoin bank -they might just be planning on running away with the money once they have enough people on board.
Unless the bank is something legit in the real world. Like having it registered and declared who owns it. A bitcoin bank will still beneficial to everyone as this could give rise to people having more services that can be useful to every user. For example, if there would be a bitcoin bank that will have ATMs all over the place that we can use to withdraw our money in fiat, or something like that.
Or maybe these "bitcoin banks" are just the same fiat banks that just adopted bitcoin.
I can't picture out somebody spending that much money for establishments, ATMs, just to build bitcoin banks, not unless if bitcoin is already booming in business. If you create a bitcoin bank, it can't be just one bank. It has to be scattered around the country or even around the world. That's tons of money
This is not necessarily required
There are regular retail banks (i.e. banks which work with individuals accepting money to deposits and loaning it to borrowers) which don't have branches or offices (barring the major office). They issue both credit and debit payment cards, you can withdraw cash through ATMs of other banks (and don't pay fees at that), i.e. they basically offer all the services which banks having physical presence offer, while they can still be said to exist entirely in cyberspace. And this is with fiat money which involves cash transactions. With Bitcoin, which is purely digital, starting a banking business should be a lot easier
Even if the bank is registered and people know who owns it, if the bank gets robbed or something bad caused your bitcoins to disappear, then the bank can't actually do anything. They can't recover it anymore because hackers will surely distribute the bitcoins to different wallets and act as if a lot of people are transacting to each other just so they cannot be traced
There are certainly risks involved but if profits heavily outweigh these risks, banks will go for Bitcoin (provided they are allowed, of course)
