I believe that the majority of us don't expect Bitcoin to become a future currency, nor are we planning to use it in our daily lives. Let's be honest here: it doesn't make too much sense to be used in that way; it's volatile and extremely valuable. Why would someone pay with Bitcoin and not a fiat currency that constantly depreciates in value? Nowadays, Bitcoin is considered an asset, similar to gold. Would you pay with gold in your daily life? Probably not. Thus, I don't see any practical reason to use it in our daily lives, unless it's for speculative purposes.
You are describing the Gresham law, when there are two different currencies in circulation the most valuable will eventually be hoarded while the less valuable will be widely used, however this only takes into account a scenario in which both fiat and bitcoin are in place at the same time, if inflation keeps growing, a point could be reached in which fiat could not buy much anymore, and that is when people will look for alternatives and gold and bitcoin could become widely used as currencies at the time.
It is not easy indeed to replace fiat currency as a means of payment. however, this can be pushed aside when fiat currency is no longer relevant to be used as a means of payment. therefore from that time needed a new alternative means of payment. it's the same as when fiat replaced the barter system as a means of exchanging goods, because the barter system was no longer relevant, money was created to value an item, and now bitcoin has emerged, and we'll just have to wait for its future developments