Well, bitcoin is still now unknown for many people because their government prohibits this kind of currency in their country, bitcoin has not reached by many people, just like me, there is no school in our country that teaches about cryptocurrency, all are only caused by self study, exploring, reading and understanding about it. There are also many people who have not considered it as money, they think that there is no money online, they think that it can be scammed because they believe that there is no money that you can get in an easy way, you have to work for it through manual things.
in any case what some people choose to do doesn't mean bitcoin is exclusive to a few. it is a free world, anybody can choose to adopt bitcoin.
Indeed, bitcoin is open for adoption for every country, all are allowed to use it no matter who they are. It depends on them if they are going to trust the bitcoin or not.