I completely agree that crypto will be the currency of the future. Cryptocurrencies are already used all over the world and constantly more and more countries begin to legalize cryptocurrencies and recognize them as official currencies, this is just a matter of time when the whole world will already fully begin to use cryptocurrencies with its full potential.
Cryptocurrency is not yet ready to be used as a legal tender in most countries. In fact, I won't personally advise that cryptocurrency should become a legal tender in any country. This is because of the issue of volatility. It would be unwise to legalize cryptocurrencies in countries especially the third world countries where basic amenities are lacking and there's high level of illiteracy.