Yes, got you intrigued, didn't it?
Bitcoin is a very good thing to have as an asset. Just like gold. Even better if I may say. It's secure, and unlike fiat money it actually exists and work is put into it to produce it. This makes it great to store value.
However, it cannot and will not replace current fiat money that the entire world it using. It just cannot.
Take paying a cup of coffee for example. To pay your coffee with bitcoins, one must get bitcoins first, either by mining or buying bitcoins with other kinds of money (*cough*fiat*cough). It ends up being a quite complicated process, don't you think?
Until we reach the point where paying for a cup of coffee is as easy with Bitcoin as it is with cash, we will never get mass adoption. And as far as I see it, there is no way of simplifying the acquiring of bitcoins.
It is very imposible that fiat money will be replace by bitcoin or any altcoin, because this is already part of our culture, maybe all electronic money like credit card and debit card will be absorbed by crypto, since this is also electronic in nature.
We always need fiat money to be used in countryside villages.