When there is a credit, there must be interest. Nobody gives away his money for nothing. If a bank gives you money, they expect a profit in return. This can't work with bitcoin because bitcoin's supply is limited and the price is too volatile. Bank can lose all of its shit while lending bitcoins.
Not really, if the bitcoin credit card provider also asks for KYC how different will this be to a bank offering credit cards? The problem will likely be when it provides the service without guarantee that they will be paid, like if it will be anonymous. We can always use bitcoin virtual credit cards anyway if we really needed a credit card.