Bitcoin will never be an alternative. What about CBDC, did you miss it? Some developed countries may be implementing a cashless financial system but will instead be CBDC or a government-created digital currency, never bitcoin. How does a decentralized currency get accepted by the government? how can a highly volatile asset become a currency? Bitcoin will be an alternative to fiat unless it is regulated and it becomes stable, but that will never happen.
Hi. I have ignored CBDC, you can't compare it with Bitcoin. Not meant negatively, but I refuse to compare it to that. If cash should no longer exist in the dimension it does today, then it is an alternative. With cash, which they can not deposit at a bank, what happen with it? Exchange of services, things and Bitcoin on a private basis.
How does a decentralized currency get accepted by the government?
Maybe never. But people are the ones who can decide it to trade.
how can a highly volatile asset become a currency?
Again, people decide that at the moment of payment. All it takes is a service or object that have a value.