Blockchain could help with a lot of tracking and that could eliminate a lot of fees for everyone around the world. I mean if blockchain somehow becomes a mainstream thing for money transactions (not just bitcoin but fiat as well for tracking) then we could literally send money all around the world from our banks and pay little to no money at all.
All we need to do is get our banks use blockchain on their data storage so that when you have money on your account and send it to someone else all they would have to do is use blockchain to move money from one address to another, every bank could have their own blockchains that nobody else uses so its fast and free, also there could be nation wide one where banks of that nation uses and maybe costs a bit more.
At some degree, Blockchain technology might trigger a small boost towards our economy. This is especially because fees will be much lower for Banks to send money across the world. As a result, Banks will be able to provide services to their customers at the lowest price possible, while achieving greater speeds like never before. Imagine using a pre-established Blockchain ledger like Ripple or even IOTA for worldwide transactions. Everything will settle within seconds (instead of days) for less than a penny (USD). Of course, the benefits will be greater with private blockchains as they won't have the bottleneck of existing public blockchains like Bitcoin and Ethereum. With a private Blockchain, governments and central banks could achieve greater scalability, which results in faster speeds and lesser fess than usual.
Still though, if a digital currency issued by a government experiences inflation over time, then we might not experience a boost in our economy after all. The only difference will be that everything will exist in the digital world, instead of conducting transactions with physical cash. But in terms of economic prosperity, it will greatly depend on how central banks properly control the supply of digital Fiat in order to reduce inflation as much as possible. With a high inflation (like Venezuela's Bolivar Currency), the economy will never improve in my opinion.
Nonetheless, it's hoped that the next economic instability would trigger a massive boost in Blockchain adoption. Once this happens, then our economy would stabilize once more as governments adopt the benefits of this revolutionary technology in every way. Then, depending on how costs are reduced and inflation is controlled, our economy could either improve over time or become worse. Only time will tell us the fate of our monetary system as we know it. Just my thoughts