They see Bitcoin as a rivary, a challenge and treat to their traditional currency existence, and it prevents fraud in the system, Bitcoin stands transparent and outstanding in all it's activities which will be difficult for the government to achieve unlike traditional currency.
Bitcoin digital currency has helped it out performed it's functions with this limited time of existence, growing far and wide for financial freedom which no currency have being able to achieve.
The government does not like the independence of Bitcoin. The government always wants the people of that country to control the financial system on which it operates. Even though the popularity of Bitcoin has increased a lot around the world, not everyone still knows about Bitcoin or there are still many who cannot trust Bitcoin. That is why the government has not yet come under such pressure from the people that they will be forced to create any positive rules and regulations regarding Bitcoin. That is why the government has not taken any direct action so far. Initially, the governments of many countries directly presented Bitcoin negatively, but now due to the increase in popularity, many powerful countries of the world are discussing about Bitcoin, many shops in some countries are accepting Bitcoin for transactions that we see in social media , all in all, the government is still in a moderate position. There is no situation where they will make Bitcoin illegal now because even if they create a policy against Bitcoin, people will use, hold, and invest in Bitcoin regardless of those policies and rules. But due to many economic complications, many countries are positive but are not able to directly approve it. So now there is no competitive relationship between Bitcoiners and the government like before. Because this increase in the price of Bitcoin is also forcing many governments of the country to think. If Bitcoin becomes one of the most valuable currencies in the world and acceptable in the future, then the countries that have Bitcoin will be ahead in the modern economy. Considering this aspect, maybe in the next few years we will see many countries thinking more positively about Bitcoin.