Saving money in a savings account is like putting money in a pocket with holes. Banks only give you interests that are lower than the inflation rate. Its how they make money. You are better off investing in ventures (Crypto currency) that give a return higher than the inflation rate.
Cryptocurrency is a currency, whereas banks are a business. Well basically that is it, that is the difference. If you really want to know more in depth differences one helps you out in a very bad inflation market where almost all currencies devalued while it gets higher because of it, the other just lets you draw loans which currency can't do, you can own as many bitcoin as you want however you can't get a loan from it, banks can give you loans tho, which is quite helpful if you really in a bad situation that could be helpful, I did get a loan once in my life that I paid for my interior of my house which I slowly paid of.
Aside from these two huge difference, nothing major that can't be explained "one is currency, the other is a business". But unfortunately we are being struck with those centralized system which is honestly not valuing our hard work and saving habits due to its inflationary supply. It is time to understand the pitfalls of our traditional fiat system and must switch over to a new system which is having the capability of rewarding if we save them.