Writing 'state' is arguably inaccurate if you read it as 'nation state', but taxation in gold by city states goes way back to early city states and more generally gold has a very long history of being accepted as payment by governments. I'm not sure about salt. I'm not convinced Rai stones are a meaningful counterpoint -- reading about them they only appear to act as money in a fairly weak and impractical sense.

Secondly, I did not say that Bitcoin has to be money to be valuable. Rather that Bitcoin is not likely to be 'money' in any serious way, and this makes the 'store of value' proposition precarious. But I don't think it's inconceivable that bitcoin might still be worth a lot 100 years from now.