its neither an asset or a commodity though its a currency, and its dosn't even need to be backed by labour because its backed by a computer
network that cannot even be matched by any amount of physical labour
even if we ignored the tax classification...
bitcoin is like intellectual property, art, graphic design, game code... which (nothing related to tax) still puts it in a description of an asset.
that being said an asset, commodity, fiat, or ANYTHING else can ALSO be a currency.. so relax, bitcoins is a currency and an asset.. it just is not a commodity..
Technically, that's not true. The thing about commodities is that there's a fixed amount of them, and in that sense, bitcoin is far more like a commodity than a currency because there will never be more than 21 million bitcoins. You can't say that (with any amount) about dollars, yen, yuan, euros, any currencies. But you can say it about: gold, oil, copper, etc.
What gets mined? Copper, gold, and in a way, oil itself if you consider drilling a form of mining. And bitcoins also get "mined", just in a technological way, rather than by digging for something. So in every way except for the fact that it treats itself like a currency, bitcoin is more like a commodity than a currency. Which, of course, doesn't mean that bitcoins can't be used as a currency.