For all it's outdatedness, Bitcoin is actually used as a currency, but typically for high value items such as real estate or private jets, as the fiat mechanisms to transfer large amounts of money, especially across borders can be terribly unreliable and costly. Bitcoin, even used in its largely original form, can be (and is) used to transfer arbitrarily large amounts of money anywhere in the world, conclusively and trustlessly, without intermediaries, within an hour, or more typically ten minutes.
There has never existed a currency that has had such properties previously.
Ah, what was the last thing you bought with bitcoin?
Or is it a currency you hold, but don't really spend? And if so why do you hold it?
Fair point. Bitcoin is a precious metal without intrinsic value :)
You can argue for the other points in this circle, but really the thing it's closest to is some sort of gold/silver that you can't use for anything else.
I guess it can be used as a currency much easier than gold can be, but in general nobody really does.
Crypto Enthusiast: "Bitcoin is a currency"
Crypto Sceptic: "Well it's not a very good currency because of X, Y & Z reasons, and nobody is spending it"
Crypto Enthusiast: "Well it's not really a currency, you need to treat it as a precious metal"
Crypto Sceptic: "But precious metals have intrinsic value - ultimately you can make something from them"
Crypto Enthusiast: "Well it's more like you can make sure your money grows rather than being shrunk through inflation - look how it's always growing!"
Crypto Sceptic: "But isn't the growth just driven by pure speculation? As in price increases just come from new people entering crypto at the bottom, and pushing it up to people who bought it earlier, who have an incentive to promote it? A bit like a ponzi scheme? I mean nobody is spending it so if it's not growing what's the point?"
Crypto Enthusiast: "Well if it stops growing that's fine because it's really a currency"