Banks are earning big profit from our deposits, they earn bigger than the interest that we get from our deposit because they put a bigger interest rate through thier borrower's or lenders, i think bank is not too far from big whales in crypto they buy or collect coins in dip and they sell in bull and they earn bigger from the holders that sell at loss they are almost the same or what? What dou you think?
There is a difference, you can't become a bank and can't offer loan/deposit to people assuming you are not a multi billionaire. But in crypto, it's different, no one stops you from buying coins during dip and selling them when they are expensive, you can even do margin trading and short sell during bear run.
But in reality, I think you should compare banks to exchanges like Binance because these exchanges sometimes manipulate futures market and liquidate users assets. In futures or margin trading, every whale can fail if exchange wants so.