I believe bitcoin and banks are well renounced investment platforms but many people prefer bitcoin investment despite is very risky because of high demands and rising price interest and banks on the other hand saves millions of people finances all over the world yet their investment interest is very small but less risky than bitcoin. Which do you preferred your money to be save in as investment? Bitcoin or bank! What's your reason?
One instance is inflation once you store your money in those banks, they give you a below 3% annual rate of interest that takes a lot of time and needs tons of money to feel the profit, additional is inflation if you invest your money in banks sooner or later the price of the goods goes up but your money still as is in the bank, instead of the cryptocurrency or the bitcoin investment you have the chance to gain profit due to market volatility but of course more way risky than the stable investment with the centralized banks. Your choice willing to risk or not still at the end of the day both sides have cons.
Everything has advantages and disadvantages, why don't we diversify but just compare to choose 1 in 2, while no one forbids us to use both? Bitcoin for investments and banks for savings and daily living expenses. That's what I did, and it worked pretty well for years. Although depositing money in the bank is like we are burying our own money because over time inflation is depreciating our currency. But there's no denying that having savings in the bank will help us in emergencies, as bitcoin doesn't always turn out to be profitable for us.