I don't think we will see such a massive change on a global scale in the next 10 - 15 years.
That said, Japan is doing its best to introduce cryptocurrencies in the mainstream. After the first bank-backed cryptocurrency exchange opened doors over there,
their regulator decided to tighten regulations (there are no bans) though about which exchanges can be officially licensed.
I think that can only be a good thing, in my opinion. They will remove any scammers and bucketshops and the truly legitimate exchanges will continue servicing people.