Moving your money into a non-local currency or store-of-value has a cost and its own risks.

If you trust an untrustable government, you lose when they betray you. If you don't trust a trustable government, you lose when you spend years and decades hedging against their betrayal and it never comes.

This is all true. The point is that a cryptocurrency gives you a choice, which you otherwise don't have, so it's useful.