in my opinion, why so far many countries have been banned from crypto currency (bitcoin) since each state has encountered the moment how it can be regulated and how we all understand that this is practically impossible, this is a new era for many countries and they are afraid of making mistakes, but just a few years later they will not have to remain options as to the lawful level of accepting it, since we all understand that people will continue to invest in it their own means, whether the state wants it or not.
The only thing I think it will make government to legalize Bitcoin is when it's centralized which I believe it's not going to happen. Many governmental organisations see bitcoin as a first means of scamming people and a way of breaking any country economy down as many individuals may prefer investing on cryptocurrency instead of creating job opportunities in the country which will lead to joblessness of it citizens and crimes will be much.