Bitcoin is already a currency but it is not yet really used like the fiat currencies. The reason is that it is not yet supported everywhere as a payment method either online or offline. That is why people still considering Bitcoin mainly as an asset, they trade and hold it for making good profits.
I am agree with you. Bitcoin is already a currency in Virtual world. As you can see, they trade their tokens or coins to have a Bitcoin. And it is number one rank as a currency in crypto world. It is also now, popular in many places and from Bitcoin you can exchange it into your national currency. They do hold, sell and buy because it is the thing that you can do when you have it.