Personally, I think that bitcoin won't become a new world currency like USD or EURO, but I think it would be widely accepted and used. But looking at some projects like El Salvador I just keep wondering, are there gonna be countries that will try making bitcoin their official currency and make all transactions using it?
The official payment currency in El Salvador is the US dollar and has been for more than 20 years, and even though Bitcoin is declared as legal tender, the percentage of people who use it in this way is very low. Legal tender does not mean that people will start using something, although many like you think that everyone pays for everything with Bitcoin in El Salvador.
So as a result, I think that bitcoin will probably stay as an asset and anonymous money. And it's not a bad thing, we need this kind of technology to exist.
It's been a long time since someone could call Bitcoin anonymous, and given that it uses a public ledger and that most users are verified on various CEXs, all those companies and various state agencies that use various tools can very easily detect who stands from which BTC addresses.