Transfering money is still possible without worrying about volatility. Imagine person A wants to send EUR to person B by converting X amount of USD. Well the two parties can decide at a point in time, at what price of bitcoin will the transfer happen. At that point sender A buys BTC worth X euros, and the receiver B can either sell btc futures of go short on an exchange that allows shorting of bitcoin so that the price of btc is locked for him. A can then transfer the bitcoin worth X to B and on receiving, B can sell BTC and close the short position. Any loss in short position is covered by gain in the BTC received. B can then withdraw Euros and the two people can split the transfer fee. Tranfer done without worring about volatility, time taken is also lower and fees are overall cheaper than bank transfers. There are cheaper ways to transfer money but this is faster for sure.

Besides the points you mentioned, banks also use our money as source of capital to buy assets that generate revenue for them. So we are funding the banks revenue to a large extent.

Banking system is a massive fraud. Sooner it ends, the better. All hail crypto!

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