If we can philosophize a bit, what is it really a digital currency? Because the official definition of the government of the Republic of Indonesia does not exist when this article was created. We take the closest definition according to Law no. 7 Year 2011 Article 1 Paragraph 1 which writes, as quoted "Currency is money issued by the Unitary State of the Republic of Indonesia hereinafter referred to as Rupiah." And if combined with Law no. 23 Year 1999 Article 2 Paragraph 2, as quoted "Rupiah currency is a legal means of payment in the territory of the Republic of Indonesia". Of the two definitions of cryptocurrency is certainly not official because it is not issued by NKRI and not a legal means of payment.So the impact of a bitcoin ban on a country can be said to defend its own currency, in the presence of bitcoin they may fear the price of its currency is not worth anymore.
I think there is no law drafted yet to regulate the cryptcurrency.
BTC as now cannot considered as a currency it just considered as an asset just like gold. It is useful only when converted to cash though some market already accepting btc as payment.
Banning the btc is a government prerogative because there is no law regulate on it. Besides there are huge of money in btc which is tax free.
It can endanger the economy actually. Investor earn and spend huge money without a tax.