yes I agree with you, but in my opinion bitcoin is a store of value. Store of value itself is something that does not depreciate over time. Usually this medium store of value is rare and cannot be easily devalued. This is what causes Bitcoin to be categorized as a store of value. The best thing you can do with bitcoins is store them so you can protect yourself from inflation. Even though bitcoin is volatile, if it is withdrawn over a longer period of time (logarithmic chart), the value of bitcoin has remained or even increased drastically in the last 10 years.
BTC does have the function of storing value, even other functions such as speculation and transactions. That is the basis of BTC being considered a currency, but what continues to be a problem today is the uniqueness of this currency which lies in a decentralized system and makes economists bothered especially those who are very pro-banking concepts. If all countries support BTC then their fiat will not sell in society, and people's current wealth will be converted to BTC, won't that disturb many people who are already in their comfort zone.