crypto has a lot of traits of a bank without the bank. Fast transactions (as opposed to carrying money to different locations), secure storage (as compared to having guards for your hoard of gold), it does not rot/burn (if you backup keys adequately) and many others.

All of those are more convenient than storing dollar bills or gold bars. So, yes, fiat has options, crypto is another kind of option and probably the most convenient for self custody, hence a very good one to avoid trusting institutions.