While decentralization is NOT the solution to everything, it will certainly make an impact over our daily life. Fiat won't be going anywhere since it's backed by mainstream governments and banks alike. That's where decentralized cryptocurrencies like Bitcoin and Ethereum come into play. They bring financial freedom to those who need it the most. It's up the person to decide whenever he/she wants to use centralized money or all the other way around.
One thing for sure is that developers don't seem to understand that decentralization is not meant for everything. Projects often use the term "decentralization" in order to attract the masses. After all, it's a "catchy" phrase in the crypto/Blockchain space. Eventually, everyone will realize that some things are meant to be centralized. Games are meant to be hosted on centralized servers due to the large number of resources they consume. If placed on a decentralized blockchain network, they would face scalability issues. The same can be said about hosting websites on the Blockchain. At least, decentralization is emerging as a "force to reckon with".
As long as the whole world doesn't become centralized, there should be nothing to worry about. Just my thoughts