You do have a point, but asset is something you own or bought that have or is valuable that can give you profit. A lot of people use it as a currency, used in payments to buy online or pay debts, but some take it as a currency but use it as an asset.

Bitcoin is best to be saved because the price is pumping every single month, that gives you profit making it a good asset. When you need money, you sell it or convert it into fiat but I don't think that will count as payment so it is more of an asset rather than a currency.