Banks are conservative over many things to minimize the risks. A new industry that allows for free transit of money in a more open society can emerge against banks. Today, the only possible project in this direction is cryptocurrency.
People think banks will have a hard time catching up, which might look like so initially, but whenever they start offering merchant side services, Coinbase and BitPay will lose market share for sure.
Banks have the best possible position to launch these services due to all the licenses they already have. They can also close bank accounts of exchanges just to grant themselves an even bigger advantage.
It wouldn't even surprise me when banks start setting up LN nodes to generate hub fees, and why wouldn't they? Banks can adapt to crypto just as easily as people here can adapt to crypto.