UK banks have only banned people from using credit cards, you can still use your debit card linked directly to your bank account. The problem is pretty simple and understandable really. If you use a credit card to buy something then you have protections against the seller if for instance the seller tries to scam you by sending you a toaster oven instead of a pair of training shoes for example.
In cryptocurrency the same protections are still there but the bank would have a pretty bad time trying to claim anything from the seller so would be left out of pocket after refunding you. Its just the banks trying to limit their own liabilities.
Can you imagine the banks trying to regain funds from bitconnect after a thousand bank customers bout ten million pounds of their tokens via credit cards?
So to clarify, your bank account that is connected to coinbase for example will see no change, as you are actually buying and selling crypto with money you actually own, whereas on a credit card you are essentially gambling someone else’s funds.
Hope that clears things up. :]