There is some country allowed bitcoin for his country but most of the country not grunted it.So it is clear that that country allowed bitcoin for this country it is a government currency and beside that country not allowed bitcoin but people use it personally there its called private currency.There are many country in the last few month banned bitcoin for his country.
yes I agree with your opinion.
Bitcoin Is Not Public in Transaction, the name of the sender and recipient or seller and buyer cannot be tracked by another person.
so I believe that Bitcoin is private.