The iPhone, or any other phone, has the intrinsic value of being usable as a computing device, entertainment device, communications device, camera, thrown weapon, etc. If you want to be pedantic about it, the components that make up the iPhone have the intrinsic values of being usable for one or more of the above functions, and the materials that go into those components have the intrinsic value of being usable in industrial/commercial products or processes.
A bitcoin literally has no use inherent use on its own. It's simply a number. The exchange of these numbers has no intrinsic value, it would be like me and Adam exchanging a 2 and a 3 (not dollars or anything other units, literally just the numbers). Any value from the exchange is an additional layer of context imposed by me and Adam on the transaction--it's not intrinsic to the bitcoin itself.
Okay, but you're just shifting the value down the line. What makes computing or entertainment valuable, other than the fact that they are things humans want?
> there’s no value in any particular set of random numbers
What is the "intrinsic value" in e.g. an iPhone? Would that value exist without humans? I would say no, it only has value because people are willing to pay for it. So I'm left wondering what principled distinction you can draw between a particular set of random numbers and a particular arrangement of metal and glass, both of which people want, to determine that one has intrinsic value and one does not.