As bitcoin is still in its early stage, it must be too early to expect bitcoin replacing traditional banking system. But, it will happen how traditional mail communication was replaced by phone and email.
Bitcoin doesn't need to replace the traditional banking system, because that's just impossible since banks and governments can progress through crypto just as much as we do. The thing here is that we shouldn't focus on what banks do, but on how we can shift away from anything that's permission based. Banks don't care about their customers, and we in the same way shouldn't care about them. It's time to move forward.
In the same way I also would like to see people move away from centralized crypto exchanges and online wallet providers. In some cases they do offer convenience, but what's that worth when you are subject to so many rules and regulations? The only thing that's difficult to combine with decentralized exchanges is fiat. Currently you can already deal with fiat on decentralized exchanges, but the trades from fiat to crypto and vice versa are not decentralized, only crypto to crypto trades are.