In the US, where cash is losing its purchasing power 7-15% a year, depending on how you measure it, many are still prepared to hold it.
Still prepared to hold it? We need cash to pay bills, buy food, buy assets, pay for vacations, pay the mortgage on investment properties, pay for maintenance and repairs of investment properties, pay real estate attorneys, pay insurance premiums, pay taxes, pay accountants, pay property managers, etc.
BTC is not accepted for any of these, only USD.
In the US, wise and prudent investors don't keep cash just lying around doing nothing out of fear to invest it, and they certainly don't risk keeping it at home out of fear of the banking system.