That argument is completely unpersuasive. These are not the same things at all. In multiple ways.

First, there is no way do duplicate bank account contents. Bank transfers are transactions: adding to your account subtracts from mine. The bitcoin ledger is infinitely copyable but doing that gives no one extra bitcoins.

Contrast that with intellectual property which is the complete opposite: information can be losslessly duplicated infinitely at no cost whatsoever to either party.

Second, bank credentials are secrets. The information is not actually meant to be widely distributed, it's meant to be known by as few people as possible, ideally one person.

The secrecy exists precisely because once information is out there there is no way to control what will be done with it. Contrast that with copyright: the monopolists want to distribute the information world wide and simultaneously fully control what people do with it. The tyranny necessary to enforce such corporate control is utterly unacceptable.

So your bank account argument in fact supports my world view by exposing how utterly schizophrenic the copyright monopolists are. They actually think they can control public information that has been disseminated far and wide. It's so out of touch with the reality of things they might as well be put out of their misery. Just abolish copyright straight up.