I think your definition is faulty: are you aware of shell money? This served as money enabling international trade for thousands of years[1], and can you say these shells have intrinsic uses?[2] These shells had value because of their properties: compact, scarce, unforgeable.
In contrast, fiat value is held because an authoritative party says value is held, e.g. Chucky Cheese tokens, or the USD. Fiat requires this authority, as in its definition: “An arbitrary order or decree.”
There are no authoritative parties declaring that Bitcoin has value, rather the market is arriving at that conclusion through decentralized operation, just as has occurred for thousands of years with gold, shells, etc.
[1] https://nakamotoinstitute.org/shelling-out/
[2] To say that a store of wealth also has uses as jewelry is redundant, IMO - storing and displaying wealth are age-old desires.