It will be so interesting how Bitcoin price behaves in the next recession.
Bitcoin also is, in some sense, similar to a fiat currency (Bitcoin has no intrinsic value) without having the typical fiat currency backing (a supporting government, complete with armies, laws and their enforcement agencies, etc. sponsoring the currency). This adds a degree of risk to Bitcoin most other currencies do not have.
Definitely I'd see it as an asset though.
You are correct that government backed currency is indeed absolutely not risk free either in all cases; if confidence in the government is lost, the "official" currency might end up as worthless, and alternatives may prosper even despite heavy-handed government efforts in some cases. There is such a thing as speculative fiat currency.
Having said that, even though forex is generally considered more risky than other sorts of investments, the likelihood of the governments of the major currency players executing the sort of serious humdingers to move their currencies into the "speculative" category seems quite low to me. (Of course, nothing in investing is guaranteed, but still...)
I'll also add that, from what I see, Bitcoin "governance" -- the technical code decisions (https://www.economist.com/blogs/freeexchange/2017/09/not-so-...) -- is somewhat in flux right now, eg the dramas over bitcoin blocksize limits. This also adds risk.