Let's look at one by one the money function on bitcoin for more details. First, as a medium of exchange. Bitcoin has no intrinsic value, so its value will depend largely on its usefulness in the economy or consumption. But in reality, today is still very small parties who use bitcoin in everyday life to make various payments. Few traders (merchants) are willing to accept bitcoin. Some countries such as Japan, for example, allow bitcoin to be used as a means of payment (not as legal tender or legal currency). But if we go to Japan, just a few, not to say very little, the store is willing to accept payment with bitcoin. Especially in other countries, including Indonesia. In other words, payments using bitcoins are currently very rare.
It has been already mentioned in the news that Bitcoin has been recognized in Japan as a legal currency. As what you had said that there are still little amount of stores accepting Bitcoin as a payment method. Maybe this is still the issue do the price itself. Japan is so much more than ready to accept cryptocurrency. It might name an age, like "Crypto Age" or "Post Coin Age". The price to be recognized as an income for stores in Japan is still not applicable yet, in my opinion, because of how unstable the price it has. Most people will simply sell Bitcoin into fiat cash. Most stores seems to step back away from embracing crypto for now.