Do yourself a favor and read "Bank 3.0" by Brett King. Or at least watch his YouTube video:
Although I doubt that Mr. King had the concept of cryptocurrencies when he wrote the book (and its predecessor "Bank 2.0"), the idea that "Banking is necessary but banks aren't" has now a lot of relevance in the crypto world.
The elimination of banks is one of the main value propositions of cryptos, and some of the big (and smart) ones already know. Just read how many banks are investing in their own blockchain products. They know that it's 'evolve or die.'
And it's not only mainstream banks. Central banks are jumping on the crypto-train too! According to this article,
67% of them were already experimenting with blockchain technology in September 2017.
(https://www.finextra.com/pressarticle/70823/sixty-seven-percent-of-central-banks-are-experimenting-with-blockchain-technology---study)
So, get yourself up to speed, find the good sources of information, and be ready for the crypto-world.