I wouldn't say they are complacent. Many banks are investing in blockchain companies, trying to benefit from cost savings that the blockchain can offer.
What possible cost savings could blockchain records offer over centralised record verification systems? How can it be more efficient to replicate the same job, thousands and thousands of times over, in a relatively data intensive format, with constantly inflating baseline processing overheads? (and the electricity to match)
Where, oh where, are these constantly hearkened "cost efficiencies" going to come from? Printing more money to cover it, perhaps? There's always some stock market types telling us that blockchain means cheaper operating costs, when it inherently means anything but.
