As what I have understand in the article the banks can defeat Bitcoin by making a currency big enough to compete with bitcoin. And this will need a big innovation since the inflation rate was one of the big disadvantage of investing in the bank. They will need to increase the earnings of their investors to earn people's trust which in turn can result for them to suffer in a great financial lost. And since they can not manipulate the bitcoin because it's decentralized it will be really hard for them to outrun the bitcoin.