Hundreds of years ago, the best technology for money was gold and the limited technology of the time forced 3 functions in to money: medium of exchange, store of value, and unit of account.
And then some genius invented currency, severing the link between medium of exchange and store of value + unit of account.
Bitcoin does essentially the same thing, except that it severs store of value from unit of account. Sure, one can use bitcoin as a means of exchange (although liquid and lightning function far better in this regard) and one could use bitcoins as a unit of account (good luck paying back a bitcoin denominates loan!) but you don’t _have_ to.
So what is the future here? Perhaps you can have a government defined unit of account still dominate in the new bitcoin world order. Money and currency have coexisted in some form since the Medici family…