That is, the reason that you can call the cops when strangers take over your kitchen is because we have a very real police force, whose are permitted (even required) to use force in order to protect your property. Property may have started out as a collective belief, but the processes put in place over the last few centuries - especially the concept of Rule of Law [3] - have made it very real.
But ISTM that crypto works outside of these norms. From what I can see, it has no effective rule of law; no possibility for the creation of an effective enforcement body. There appear to be no consistently applied consequences of cheating, either intentional (eg, rug-pulls) or not. People seem to steal money using crypto scams all the time [1]; from what I've seen of it, the world of crypto seems to pretty much embody my personal, nightmare interpretation of anarcho-capitalism [2].
So while I agree that property is a collective belief in theory, in practice it has the rule of law, the legitimacy of the state, and the monopolisation of force supporting it. Crypto seems to have none of these things supporting it; I'm yet to be convinced that it is even, actually, property.
[0] https://en.wikipedia.org/wiki/Legitimacy_(political)
[1] https://web3isgoinggreat.com
