Yes OP, it is. It's so reliable, but the government sees it as a threat to the stability of their economy. You know it isn't centralized, and that's the coolest part, but the government can't leave the whole monetary system Into a digitalized program. Knowing how complex it is, a lot of people would find it difficult to adapt to it.
Another thing is the use of Bitcoin for illegal activities due to it being pseudonymous making it difficult for law enforcement agencies to trace and track the flow of funds.
So In as much as Bitcoin is so good and advantageous, it also has its drawbacks and limitations ( which include many more than I've talked about by the way) making it only an alternative at the end of the day.