Why would anyone choose fiat over Bitcoin? Unless it was your average Joe that thinks that cryptos are play made up money. But you're not going to find such people here. I remember telling my coworkers, showing them, "Look, Bitcoin was worth this in 2011, it is worth this now." And it would just not click. It just went in one ear and out the other.
But anyway, most of my money is in cryptos, and I want to diversify it in other coins. The more Bitcoins I have, the easier it is to do.
Bitcoin is more important in my point of view. If you are more interested in paper money than I will suggest euro instead of dollars. However, future of money lies in digital currencies. Bitcoin is an asset as well as currency. If you will invest here at the moment, you are going to make big profits in the near future and as it is grabbing fame on daily basis, one day only this will be medium of exchange.