Will bitcoin eventually dominate the world economy and replace traditional currencies?
I don't think it's ever possible. Now Bitcoin is the 7th largest currency in the world, that's great, but we shouldn't be so optimistic. Bitcoin can't replace fiat because of many reasons.
Otherwise bitcoin can co exist with fiat and bitcoin can also be used as store of value. It's not always to replace the another kind of currency but people can use bitcoin as the best digital gold that can be used to create a payment system too. Bitcoin has so many advantages over another currency or commodity.
I agreed with you about that dude