Earlier quoted context omitted.
Everyone who had overseas bank accounts in 2002 Argentina did just fine. Bitcoin on a foreign exchange or in a self-custody wallet would also be just fine. Getting a foreign bank account is too expensive for your average Argentinian because you have to show up in person to set it up, but a self-custody wallet can be had on any minimal smart phone.
People who wanted self-custody could also keep their money under the mattress. The reason why most cryptocurrency users do not do that is because there are many failure modes which result in your money being gone forever. You also left out the other part of the overseas bank accounts: you have to be rich enough not to need to touch the money — otherwise you'll run into the various restrictions on transfers. The same…
Keeping money under the mattress is done in Argentina, but is not that common for large amounts since getting your hands on physical dollar bills in quantity in Argentina is extremely difficult. It's also difficult to determine if the bills are counterfeit, but Bitcoin does not have this problem.
I have heard stories of people paying their living expenses in Bitcoin and the people who receive it love that because the Argentinian peso is constantly devaluing. The person they pay spends all their money on the person paying them bitcoin because the currency devalues like crazy anyway, so it's much better to pay Pesos and save in Bitcoin.