As far as I know, bitcoin is now considered as an asset and a payment method in some country. It's a very long way for bitcoin to be a currency.
In my opinion, bitcoin maybe is considered as a payment method but not asset now
.. U can trade, send, and give bitcoin and they now depend on USD or some "currency".. We determind "asset value" by BTC not BTC value = anything like Gold, Silver, Oil...
For me, bitcoin belongs to both. It is a virtual currency or an electronics money and it is also an asset, if the bitcoin is not yet in your wallet so its right to call it as a currency circulated over the internet and if the time comes that you already earned, buy or generally you own bitcoin then it will become an asset, as we know that asset are those everything that has a precious value and can be convertible to cash.