Yes, I agree eith this people look up to the stability of their money and Bitcoin might not be able to satisfy it due to the fact that Bitcoin's fluctuation rapidly changing and I think it is not suitable in performing transactions like paying bills which may be one of the possible uses of Bitcoin if it was accepted locally and of course the government would not allow this kind of system that might overpower them.
The stability factor is indeed one of the reasons why Bitcoin cannot become a global currency, In addition, the decentralization factor owned by Bitcoin I think also includes other reasons. We know that Bitcoin is a decentralized system where the Government or other third parties cannot regulate and control Bitcoin.
I think the decentralized system of bitcoin could be a big issue here when it comes to being a currency because it cannot be regulated by any government. I think having a global currency is impossible since in different countries we have different standards we cannot buy something that is at the same price in other countries. We are already using bitcoin as a global currency since anyone could use it in the world and send a transaction but just an alternative currency.