No, this is not true.  There is fundamental value, which is economic utility.  Food has economic utility.  The joy in your life is higher if you have food than if you don't.  And economic utility is related to personal joy (or removal of personal suffering).  There ARE a lot of things that are perceived as bringing joy, and they are the basis of what is called economic utility: a house, food, entertainment,....  everything we want as end consumer.  Our desires.  Price results from economic utility confronted with scarcity.  Food is not very expensive (even though it is just as useful) if there's plenty ; food becomes very expensive if there's almost none and we fight over it.

Assets are indirect owners of provision of economic utility.  Production capital has indirect economic utility, because it can provide the market with consumption goods that increase joy of consumers.  You can package this more and more, and the complicated derivation of all these things down to "joy" is what is the fundamental of an asset.  Bitcoin has none.