Actually no item has any worth except what the receiver of said item deems it, including fiat.
Example.
In the US the following bill is worthless to me , and I would prefer an altcoin on an exchange to it, because for me the altcoin would be easier to exchange.
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However a Canadian would feel differently.
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But in some places the Fiat is not worth the paper it is printed on.
Every form of money always will be
Perceived Value.
Very true. Every monetary asset (that is, a collectible that has no other function than to be acquired against value, to be left later against value) is an infinitely recursive belief system: you accept it (against value you hand over) because you believe that Joe will accept it from you (you obtaining value from Joe) ; and you believe that, because you believe that Joe will believe that Jack will accept it, who believes it because Mary will accept it etc...
So all value a monetary asset has, is pure belief, because by definition, the monetary asset itself has no or almost no intrinsic value (that is, without it being able to be exchanged against something else, you cannot obtain much satisfaction from it: you cannot eat it, you cannot fuck it, you cannot enjoy it, you cannot use it to produce goods or services: you can ONLY trade it for something else). Not all collectibles are totally devoid of intrinsic value: gold is shiny and you can make jewels of it, and it has some technological use ; paintings can be nice to decorate your house with, ...
But fiat (apart from burning in the stove as a fuel) is almost intrinsically worthless, and crypto (apart from serving as an immutable ledger) is also almost intrinsically worthless. Which doesn't mean that it cannot have high monetary (belief) value.
The monetary belief value exists, because the function of *store of value* (in the short term: currency, in the long term: savings) is economically very useful. There is globally (and locally) a certain demand for store of value, which can be variable according to circumstances. People want to store a certain amount of value for a certain period at a given time and location. The actual market value a monetary asset will obtain, will be given by how much will be its market share in this market of demand for store of value. If you want to store the value of a car for say, 6 months, you have several options to do so: you can use fiat, stock, paintings, bitcoin, altcoins, gold, ....
The different monetary assets will have market prices according to how much value is to be stored, and what share of that stored value has been elected to be in said monetary asset.
Unfortunately, monetary assets also attract another kind of value, which is what I call 'greater fool theory'. The idea there is not to "put aside value for later" (the economic demand for store of value between two trading acts), but rather to hope for the increase in market value of a given store of value. That's speculation. Speculation becomes problematic if it becomes the main demand for a monetary asset, and hence if it determines the price of that asset, instead of "surfing on the legit demand for it economically wise". If the price of a monetary asset is principally determined by expectations of higher price, then we are in the typical black tulip style of speculative bubble. My idea is that bitcoin and most altcoins are mainly suffering from that.