the same argument can be said about literally every non-crypto currency. A US dollar doesn't have any "value" other than the small amount of heat you get if you burn your paper bills.
You pay taxes in USD, USD is legal tender for debts, you are incentivized to borrow in USD and finally because the dollar is widely accepted even beyond the borders of the US.
Money is really only meant to be a relationship between people which tracks how much they owe each other, the value isn't derived from money itself but from the network effects of many humans engaging in economic activity.
5% inflation obviously ruins the store of value aspect but it hasn't stopped anyone from sending or accepting inflating money. The idea that a merchant would refuse USD because it lost 95% of its value compared to eighty years ago or whatever is unheard of and doesn't seem to bother merchants as long as they can re-adjust prices quickly enough.
The last one is the most important. If everyone in El Salvador accepts Bitcoin then Bitcoin will act as money just like any other currency.
> same argument can be said about literally every non-crypto currency. A US dollar doesn't have any "value" other than the small amount of heat you get if you burn your paper bills.
Or the food and fuel one can import with it, which one can't with Bitcoin.