You have listed the technological advantages of a mutual payment system, for a society that is interested and ready for such a model. BUT... The problem is that the advantages of cryptocurrency are also its disadvantages.
Now let's return to the issue of war, which I can judge quite objectively, since in my country there is a direct war, the loss of cryptocurrencies in such a situation is a very real picture. Sorry the example is very harsh, but this is our reality in Ukraine. A person was sitting at home, went to the store, a missile launched by Russian terrorists arrives in a residential neighborhood, a person dies on the street - that's it, the person is gone, and there is no access to his crypto-assets. In this situation, in relation to fiat, whether it is a bundle of money or a credit card, his relatives (children, wife) can get access to them. Crypto-assets - never again.
The situation is different - your city is surrounded or captured by Russian terrorists - no communication, laptops, cell phones are confiscated.... You have to eat somehow, you have to buy food with something. How can cryptocurrencies help you here if you don't have access to them? Okay. You find Starlink, you connect. И ? Best case scenario, you withdraw the money to a bank card. But in an occupied city, Russian invaders destroyed and looted banks, destroyed ATMs ...
In a word - crypto-assets in such a difficult situation - not the best financial assistant.