Fiat is still more better than bitcoin with the following reasons:

1) population: Fiat is still more popular than bitcoin in the world. There are some countries in the world, don't care to know bitcoin in their country based, they are use to fiat.
2) control by the government: Fiat money is control by the government. Government know when to make it pump or dump because they have the power to do that in the country.
3) Very easy for uneducated people to operate .